ChemWiki - User contributions [en]

MO:hm1017

2019-05-24T15:34:50Z

Hm1017: /* MO73 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

(1) strong directed p-p sigma overlap, hence strong anti-bonding interaction

(2) weak p-p pi overlap, hence weak bonding interaction

(3) weak long range through space p-p bonding interactions

(4) nodes on atoms less important

In conclusion, it is highly antibonding.

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

(1) strong directed p-p sigma ovrelap, hence strong anti-bonding interaction

(2) weak p-p pi antibonding interactions

(3) medium non-directed p-p overlap bonding interaction

(4) weak long range through space antibonding interactions

(5) medium non-directed p-p through space anti-bonding interaction

(6) nodes between atoms increase anti-bonding character

In conclusion, it is highly anti-bonding.

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

(1) strong directed p-p sigma ovrelap, hence strong bonding interaction

(3) weak long range through space bonding interactions

(4) weak p-p pi bonding interactions

In conclusion, it is highly bonding.

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:34:00Z

Hm1017: /* MO70 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

(1) strong directed p-p sigma overlap, hence strong anti-bonding interaction

(2) weak p-p pi overlap, hence weak bonding interaction

(3) weak long range through space p-p bonding interactions

(4) nodes on atoms less important

In conclusion, it is highly antibonding.

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

(1) strong directed p-p sigma ovrelap, hence strong anti-bonding interaction

(2) weak p-p pi antibonding interactions

(3) medium non-directed p-p overlap bonding interaction

(4) weak long range through space antibonding interactions

(5) medium non-directed p-p through space anti-bonding interaction

(6) nodes between atoms increase anti-bonding character

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

(1) strong directed p-p sigma ovrelap, hence strong bonding interaction

(3) weak long range through space bonding interactions

(4) weak p-p pi bonding interactions

In conclusion, it is highly bonding.

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:33:51Z

Hm1017: /* MO70 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

(1) strong directed p-p sigma overlap, hence strong anti-bonding interaction

(2) weak p-p pi overlap, hence weak bonding interaction

(3) weak long range through space p-p bonding interactions

(4) nodes on atoms less important

In conclusion, it is highly antibonding.

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

(1) strong directed p-p sigma ovrelap, hence strong anti-bonding interaction

(2) weak p-p pi antibonding interactions

(3) medium non-directed p-p overlap bonding interaction

(4) weak long range through space antibonding interactions

(5) medium non-directed p-p through space anti-bonding interaction

(6) nodes between atoms increase anti-bonding character

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

(1) strong directed p-p sigma ovrelap, hence strong bonding interaction

(3) weak long range through space bonding interactions

(4) weak p-p pi bonding interactions

in conclusion, it is highly bonding.

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:31:01Z

Hm1017: /* MO73 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

(1) strong directed p-p sigma overlap, hence strong anti-bonding interaction

(2) weak p-p pi overlap, hence weak bonding interaction

(3) weak long range through space p-p bonding interactions

(4) nodes on atoms less important

In conclusion, it is highly antibonding.

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

(1) strong directed p-p sigma ovrelap, hence strong anti-bonding interaction

(2) weak p-p pi antibonding interactions

(3) medium non-directed p-p overlap bonding interaction

(4) weak long range through space antibonding interactions

(5) medium non-directed p-p through space anti-bonding interaction

(6) nodes between atoms increase anti-bonding character

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:22:52Z

Hm1017: /* MO74 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

(1) strong directed p-p sigma overlap, hence strong anti-bonding interaction

(2) weak p-p pi overlap, hence weak bonding interaction

(3) weak long range through space p-p bonding interactions

(4) nodes on atoms less important

In conclusion, it is highly antibonding.

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Hmo6.png

2019-05-24T15:13:09Z

Hm1017:

File:Hmo3.png

2019-05-24T15:12:52Z

Hm1017:

MO:hm1017

2019-05-24T15:12:43Z

Hm1017: /* MO70 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

====MO70====
[[File:hmo3.png|thumb|center|MO70]]
[[File:hmo6.png|thumb|center|MO70]]

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Hmo5.png

2019-05-24T15:12:02Z

Hm1017:

File:Hmo2.png

2019-05-24T15:11:46Z

Hm1017:

MO:hm1017

2019-05-24T15:11:35Z

Hm1017: /* MO73 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

====MO73====
[[File:hmo2.png|thumb|center|MO73]]
[[File:hmo5.png|thumb|center|MO73]]

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:11:11Z

Hm1017: /* MO74 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo4.png|thumb|center|MO74]]

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:10:53Z

Hm1017: /* MO74 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]
[[File:hmo2.png|thumb|center|MO74]]

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:10:40Z

Hm1017: /* MO74 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1.png|thumb|center|MO74]]

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:10:16Z

Hm1017: /* MO74 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:09:52Z

Hm1017: /* MO calcualtion on the lowest energy isomer */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Hmo4.png

2019-05-24T15:08:22Z

Hm1017:

File:Hmo1.png

2019-05-24T15:08:01Z

Hm1017: Hm1017 uploaded a new version of File:Hmo1.png

File:Hmo1.png

2019-05-24T15:07:31Z

Hm1017:

MO:hm1017

2019-05-24T15:06:55Z

Hm1017: /* MO calcualtion on the lowest energy isomer */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====
[[File:hmo1|thumb|center|MO74]]
[[File:hmo4|thumb|center|MO74]]

====MO73====
[[File:hmo2|thumb|center|MO73]]
[[File:hmo5|thumb|center|MO73]]

====MO70====
[[File:hmo3|thumb|center|MO70]]
[[File:hmo6|thumb|center|MO70]]

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T15:04:31Z

Hm1017: /* MO calcualtion on the lowest energy isomer */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

3 MOs ranging from highly bonding to highly antibonding

====MO74====

====MO73====

====MO70====

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T13:16:18Z

Hm1017: /* MO calcualtion on the lowest energy isomer */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===
Isomer 4 is the lowest energy isomer.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Alhs5.LOG

2019-05-24T12:57:23Z

Hm1017:

MO:hm1017

2019-05-24T12:57:05Z

Hm1017: /* Isomer 5 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhs5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhs5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T12:41:02Z

Hm1017: /* The dissociation energy for the lowest energy conformer into 2AlCl2Br */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|optimised AlCl2Br]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) = -3734.74851982 a.u.

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = 0.36578516 a.u. = 960 kJ/mol

The product is less stable than the isolated monomers, due to the positive ΔE.

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-24T12:37:12Z

Hm1017: /* The dissociation energy for the lowest energy conformer into 2AlCl2Br */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>MHSMONOMER.LOG</uploadedFileContents>
</jmolApplet></jmol>

[[File:hsm9.png|thumb|center|NI3]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) =

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] =

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = a.u. = kJ/mol

The product more or less stable than the isolated monomers?

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:MHSMONOMER.LOG

2019-05-24T12:36:50Z

Hm1017:

File:Hsm9.png

2019-05-24T12:36:06Z

Hm1017:

MO:hm1017

2019-05-24T12:35:49Z

Hm1017: /* The dissociation energy for the lowest energy conformer into 2AlCl2Br */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
<jmol><jmolApplet>
<title>optimised AlCl2Br (B3LYP/6-31G(d,p))</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_monomer_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

[[File:hsm9.png|thumb|center|NI3]]

The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) =

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] =

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = a.u. = kJ/mol

The product more or less stable than the isolated monomers?

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T23:34:04Z

Hm1017: /* The relative stability of these conformers with respect to the bridging ions */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===
For the two bridge atoms, if they are different (one Br and one Cl), the energy will be more negative. Then it will be more stable.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) =

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] =

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = a.u. = kJ/mol

The product more or less stable than the isolated monomers?

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T23:22:59Z

Hm1017: /* The dissociation energy for the lowest energy conformer into 2AlCl2Br */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) =

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] =

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] = a.u. = kJ/mol

The product more or less stable than the isolated monomers?

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T23:21:38Z

Hm1017: /* Is the product more or less stable than the isolated monomers? */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===
The lowest energy conformer is the isomer 4, which has the most negative energy.

E(AlCl2Br) =

E(Al2Cl4Br2) = -7469.13125448 a.u.

ΔE = E(Al2Cl4Br2) - [E(AlCl2Br)+E(AlCl2Br)] =

The product more or less stable than the isolated monomers?

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T23:15:01Z

Hm1017: /* The dissociation energy for the lowest energy conformer into 2AlCl2Br */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The relative stability of these conformers with respect to the bridging ions===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T23:13:19Z

Hm1017: /* The relative stability of these conformers with respect to the bridging ions */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The energy of the isomers with (a) 2 bridging Br ions and (b) the isomer with trans terminal Br and bridging Cl ions===

(a) is the isomer 1, with the energy -7469.09028905 a. u.

(b) is the isomer 3, with the energy -7469.13122002 a. u.

The energy of (b) is a little more negative, thus it is more stable. This is due to the steric factor. In the isomer 3, the two larger Br groups are far away from each other, so there is less repulsion between their lone pairs.

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:59:03Z

Hm1017: /* Isomer 5 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:58:44Z

Hm1017: /* Isomer 4 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:57:58Z

Hm1017: /* Isomer 3 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610204 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:57:04Z

Hm1017: /* Isomer 1 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:56:55Z

Hm1017: /* Isomer 2 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is 19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is -19610095 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:56:03Z

Hm1017: /* The five possible isomers */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

1 a.u. = 2625.5 kJ/mol, hence energy is 19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:55:49Z

Hm1017: /* Isomer 1 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.
1 a.u. = 2625.5 kJ/mol, hence energy is 19610097 kJ/mol

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Alhm5.LOG

2019-05-23T17:52:00Z

Hm1017:

File:Hsm8.png

2019-05-23T17:51:46Z

Hm1017:

MO:hm1017

2019-05-23T17:51:35Z

Hm1017: /* Isomer 5 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 5</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm5.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm5.LOG| Alhm5.LOG]]
[[File:hsm8.png|thumb|center|Isomer5]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000197 0.000450 YES
RMS Force 0.000051 0.000300 YES
Maximum Displacement 0.000621 0.001800 YES
RMS Displacement 0.000365 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:48:23Z

Hm1017: /* Isomer 4 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13125 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

File:Hsm7.png

2019-05-23T17:47:23Z

Hm1017:

File:Alhm4.LOG

2019-05-23T17:47:06Z

Hm1017:

MO:hm1017

2019-05-23T17:46:52Z

Hm1017: /* Isomer 4 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 4</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm4.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm4.LOG| Alhm4.LOG]]
[[File:hsm7.png|thumb|center|Isomer4]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000025 0.000450 YES
RMS Force 0.000010 0.000300 YES
Maximum Displacement 0.000375 0.001800 YES
RMS Displacement 0.000174 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:45:02Z

Hm1017: /* Isomer 3 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000101 0.000450 YES
RMS Force 0.000034 0.000300 YES
Maximum Displacement 0.001656 0.001800 YES
RMS Displacement 0.000719 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

MO:hm1017

2019-05-23T17:43:50Z

Hm1017: /* Isomer 1 */

==BH3==
===B3LYP/6-31G(d,p)===
<pre> Item Value Threshold Converged?
Maximum Force 0.000158 0.000450 YES
RMS Force 0.000079 0.000300 YES
Maximum Displacement 0.000622 0.001800 YES
RMS Displacement 0.000311 0.001200 YES </pre>

Frequency fileː [[Media:HUISHU_BH3_631_D3H_FREQ.LOG| HUISHU_BH3_631_D3H_FREQ.LOG]]

<pre> Low frequencies --- -0.2456 -0.1129 -0.0054 44.0270 45.1846 45.1853

Low frequencies --- 1163.6049 1213.5924 1213.5951 </pre>
<jmol><jmolApplet>
<title>BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrational spectrum for BH3===
{| class="wikitable" border="1"
|+ BH3 vibrational spectrum
! wavenumber(cm-1) !! Intensity (arbitrary units) !! symmetry !! IR active? !! type
|-
| 1163.60 || 92 || E' || yes || out-of-plane bend
|-
| 1213.59 || 14 || A2" || yes || bend
|-
| 1213.60 || 14 || E' || yes || bend
|-
| 2580.15 || 0 || E' || no || symmetric stretch
|-
| 2713.12 || 126 || A1' || yes || asymmetric stretch
|-
| 2713.12 || 126 || E' || yes || asymmetric stretch
|}
[[File:huishu1.png|thumb|center|Display Vibrations]]
[[File:huishu2.png|thumb|center|IR Spectrum]]

A vibrational mode absorbs infrared light when it is in a periodic change in the dipole moment of the molecule. Such vibrations are said to be infrared active. In general, the greater the polarity of the bond, the stronger its IR absorption. The symmetric stretch in BH3 (2580.15 cm-1) does not result in a change in dipole moment, and therefore does not result in any absorption of light.

===PP and basis sets===

Frequency file: [[Media:HUISHU_BH3_631_D3H.LOG| HUISHU_BH3_631_D3H.LOG]]
[[File:huishu4.png|thumb|center|Summary]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000161 0.000450 YES
RMS Force 0.000105 0.000300 YES
Maximum Displacement 0.000638 0.001800 YES
RMS Displacement 0.000418 0.001200 YES </pre>

<jmol><jmolApplet>
<title>optimised BH3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HUISHU_BH3_631_D3H.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.1927

===MOs for BH3===
There is no significant differences between the real and LCAO MOs. Hence when we draw the LCAO MOs, the real MOs can be used for a reference.
[[File:huishu7.png|440px|thumb|center|MO diagram]]

{|
|+ Real MOs
|-
|[[File:hm1.png|150px|thumb|center|1a1']] || [[File:hm2.png|150px|thumb|center|2a1']] || [[File:hm3.png|150px|thumb|center|1e']] || [[File:hm4.png|150px|thumb|center|1e']]
|-
|[[File:hm5.png|150px|thumb|center|1a2' '' ']]
|[[File:hm6.png|150px|thumb|center|3a1']]
|[[File:hm7.png|150px|thumb|center|2e']]
|[[File:hm8.png|150px|thumb|center|2e']]
|}

===Association energies: Ammonia-Borane===
<jmol><jmolApplet>
<title>NH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 1.0179

<jmol><jmolApplet>
<title>NH3BH3 B3LYP/6-31G(d,p)</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NH3BH3_631_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance are 1.2097(B-H), 1.6686 (B-N), 1.0184 (N-H)

[[File:hsm1.png|thumb|center|NH3]]
[[File:hsm2.png|thumb|center|NH3BH3]]

<pre> NH3
Low frequencies --- -32.4235 -32.4224 -11.4276 -0.0047 0.0113 0.0475
Low frequencies --- 1088.7628 1694.0251 1694.0251
Item Value Threshold Converged?
Maximum Force 0.000092 0.000450 YES
RMS Force 0.000039 0.000300 YES
Maximum Displacement 0.000305 0.001800 YES
RMS Displacement 0.000102 0.001200 YES </pre>
Frequency file for NH3ː [[Media:HSM_NH3_631_FREQ.LOG| HSM_NH3_631_FREQ.LOG]]

<pre> NH3BH3
Low frequencies --- -25.5743 -13.3444 0.0008 0.0009 0.0012 10.9831
Low frequencies --- 262.9367 631.1057 637.2215
Item Value Threshold Converged?
Maximum Force 0.000273 0.000450 YES
RMS Force 0.000060 0.000300 YES
Maximum Displacement 0.001506 0.001800 YES
RMS Displacement 0.000384 0.001200 YES </pre>
Frequency file for NH3BH3ː [[Media:HSM_NH3BH3_631_FREQ.LOG| HSM_NH3BH3_631_FREQ.LOG]]

E(NH3) = -56.55777 a.u.

E(BH3) = -26.61532 a.u.

E(NH3BH3) = -83.22469 a.u.

ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u.

1 a.u. = 2625.5 kJ/mol

Hence ΔE = E(NH3BH3) - [E(NH3)+E(BH3)] = -0.05160 a.u. = -135.48 kJ/mol

It is a medium bond. The dative bond is weaker than commom covalent bond.

==NI3==
B3LYP/6-31G(d,p)

<jmol><jmolApplet>
<title>optimised NI3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>HSM_NI3_freq.LOG</uploadedFileContents>
</jmolApplet></jmol>
The optimized distance is 2.1836

Frequency file: [[Media:HSM_NI3_freq.LOG| HSM_NI3_freq.LOG]]
[[File:hsm3.png|thumb|center|NI3]]
<pre> Low frequencies --- -12.7349 -12.7287 -6.2860 -0.0040 0.0188 0.0634
Low frequencies --- 101.0320 101.0328 147.4112

Item Value Threshold Converged?
Maximum Force 0.000063 0.000450 YES
RMS Force 0.000038 0.000300 YES
Maximum Displacement 0.000478 0.001800 YES
RMS Displacement 0.000273 0.001200 YES </pre>

==Project - Al2Cl4Br2==
===The five possible isomers===
====Isomer 1====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 2====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.08959 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 2</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm2.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm2.LOG| Alhm2.LOG]]
[[File:hsm5.png|thumb|center|Isomer2]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000059 0.000450 YES
RMS Force 0.000020 0.000300 YES
Maximum Displacement 0.001628 0.001800 YES
RMS Displacement 0.000580 0.001200 YES </pre>

====Isomer 3====
B3LYP/6-31G(d,p)

Symmetryː C1

Energyː -7469.13122 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 3</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm3.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm3.LOG| Alhm3.LOG]]
[[File:hsm6.png|thumb|center|Isomer3]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 4====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

====Isomer 5====
B3LYP/6-31G(d,p)

Symmetryː CS

Energyː -7469.09029 a.u.

<jmol><jmolApplet>
<title>Al2Cl4Br2 Isomer 1</title>
<color>black</color>
<size>200</size>
<uploadedFileContents>Alhm1.LOG</uploadedFileContents>
</jmolApplet></jmol>
File: [[Media:Alhm1.LOG| Alhm1.LOG]]
[[File:hsm4.png|thumb|center|Isomer1]]
<pre> Item Value Threshold Converged?
Maximum Force 0.000010 0.000450 YES
RMS Force 0.000004 0.000300 YES
Maximum Displacement 0.000798 0.001800 YES
RMS Displacement 0.000279 0.001200 YES </pre>

===The relative stability of these conformers with respect to the bridging ions===

===The dissociation energy for the lowest energy conformer into 2AlCl2Br===

===Is the product more or less stable than the isolated monomers?===

===MO calcualtion on the lowest energy isomer===

==Reference==
1. http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf