View source for Rlk3917 inorganic computational

== BH<sub>3</sub> ==
B3LYP 6-31Gd/p

<pre> BH3 frequency and MOs
File Name = RKW-BH3-FREQ
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = 6-31G(d,p)
Charge = 0
Spin = Singlet
E(RB3LYP) = -26.61532348 a.u.
RMS Gradient Norm = 0.00007899 a.u.
Imaginary Freq = 0
Dipole Moment = 0.0000 Debye
Point Group = D3H
Job cpu time:       0 days  0 hours  0 minutes 36.0 seconds.
 </pre>

<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>



Link to [[Media:RKW-BH3-FREQ.LOG|log file]]

<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>RKW-BH3-FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Vibrations===

{| class="wikitable"
! scope="col"| #
! scope="col"| Frequency / cm<sup>-1</sup>
! scope="col"| Intensity
|-
|1
|1164
|92
|-
|2
|1214
|14
|-
|3
|1214
|14
|-
|4
|2580
|0
|-
|5
|2713
|126
|-
|6
|2713
|126
|}

[[File:rkw-BH3.png|PNG]]

The 4th vibration is IR inactive, as this corresponds to the symmetrical stretch of all three B-H bonds.

[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 17:38, 8 May 2019 (BST) Symmetry labels and assignments (i.e.: type of mode, out-of-plane bend, in-plane bend, etc.) are missing. Also, why are there only three peaks in the IR spectrum, but 6 modes in the table?

[[File:rkw-BH3_stretch.png|400px|PNG]]

===MOs===

[[File:rkw-BH3-MO-diagram.png|800px|PNG]]

Molecular Orbital diagram from: P. Hunt's tutorial notes, http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf, (accessed May 2019)

The calculated molecular orbitals do not deviate significantly from those derived through a qualitative approach, showing that it is a powerful tool for the approximate determination of molecular orbitals.


[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 17:43, 8 May 2019 (BST) Note that the 3a1 and 2e' MOs have do deviate somewhat from qualitative MO theory. Try to think about how they deviate.

==NH<sub>3</sub> & NH<sub>3</sub>BH<sub>3</sub>==
===NH<sub>3</sub>===
B3LYP 6-31Gd/p

<pre>
NH3
File Name = NH3
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = 6-31G(d,p)
Charge = 0
Spin = Singlet
E(RB3LYP) = -56.55776873 a.u.
RMS Gradient Norm = 0.00000323 a.u.
Imaginary Freq = 0
Dipole Moment = 1.8465 Debye
Point Group = C3V
Job cpu time:       0 days  0 hours  0 minutes 57.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000006     0.000450     YES
 RMS     Force            0.000004     0.000300     YES
 Maximum Displacement     0.000014     0.001800     YES
 RMS     Displacement     0.000009     0.001200     YES
</pre>

Link to [[Media:Rkw-NH3.LOG|log file]]

<pre>
Low frequencies ---   -0.0127   -0.0022    0.0006    7.1034    8.1048    8.1051
 Low frequencies --- 1089.3834 1693.9368 1693.9368
</pre>

<jmol><jmolApplet>
  <title>NH3</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-NH3.LOG</uploadedFileContents>
</jmolApplet></jmol>

===NH<sub>3</sub>BH<sub>3</sub>===

B3LYP 6-31Gd/p

<pre>
NH3BH3
File Name = NH3BH3
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = 6-31G(d,p)
Charge = 0
Spin = Singlet
E(RB3LYP) = -83.22468892 a.u.
RMS Gradient Norm = 0.00005935 a.u.
Imaginary Freq = 0
Dipole Moment = 5.5651 Debye
Point Group = C3V
Job cpu time:       0 days  0 hours  0 minutes 28.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000121     0.000450     YES
 RMS     Force            0.000057     0.000300     YES
 Maximum Displacement     0.000570     0.001800     YES
 RMS     Displacement     0.000318     0.001200     YES
</pre>

Link to [[Media:Rkw-NH3BH3.LOG|log file]]

<pre>
Low frequencies ---   -0.0253   -0.0031    0.0004   17.0476   17.0501   36.9367
 Low frequencies ---  265.7521  632.2129  639.3374
</pre>

<jmol><jmolApplet>
  <title>NH3BH3</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-NH3BH3.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Relative Energy===
E(BH3)=-26.61532 a.u.
E(NH3)=-56.55777 a.u.
E(NH3BH3)=-83.22469 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)]=-83.22469-(-26.61532-56.55777)
=-0.05160 a.u
=-135 kJmol<sup>-1</sup>


This is a weak bond, compared with a C-C bond in the analagous ethane which is ~360 kJmol<sup>-1</sup>.

[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 17:49, 8 May 2019 (BST) You need to add a reference here for the literature value you cited.

==NI<sub>3</sub>==
B3LYP/6-31G(d,p)LANL2DZ

Link to [[Media:Rkw-NI3-OPTIMISATION.LOG|log file]]

<pre>
NI3 optimisation
File Name = NI3-OPTIMISATION
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = Gen
Charge = 0
Spin = Singlet
E(RB3LYP) = -88.80858845 a.u.
RMS Gradient Norm = 0.00004431 a.u.
Imaginary Freq = 
Dipole Moment = 1.3092 Debye
Point Group = C3V
Job cpu time:       0 days  0 hours  0 minutes 27.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000102     0.000450     YES
 RMS     Force            0.000075     0.000300     YES
 Maximum Displacement     0.000858     0.001800     YES
 RMS     Displacement     0.000629     0.001200     YES
</pre>

<pre>
Low frequencies ---  -12.3845  -12.3781   -5.6129   -0.0040    0.0194    0.0711
 Low frequencies ---  100.9307  100.9314  147.2333
</pre>


<jmol><jmolApplet>
  <title>NH3BH3</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-NI3-OPTIMISATION.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I bond length = 2.184 Å

==Project==

[[File:Rkw-Isomers-and-symmetry.PNG|PNG]]

===Isomer 1===
Method:B3LYP/ Al 6-31G(d,p); Cl, Br LANL2DZ

Link to [[Media:Rkw-AL2_1.LOG|log file]]

<pre>
Al2_1
File Name = AL2_1
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = Gen
Charge = 0
Spin = Singlet
E(RB3LYP) = -571.43283094 a.u.
RMS Gradient Norm = 0.00002738 a.u.
Imaginary Freq = 0
Dipole Moment = 0.0000 Debye
Point Group = D2H
Job cpu time:       0 days  0 hours  0 minutes 21.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000034     0.000450     YES
 RMS     Force            0.000015     0.000300     YES
 Maximum Displacement     0.000402     0.001800     YES
 RMS     Displacement     0.000113     0.001200     YES
</pre>

<pre>
Low frequencies ---   -2.5130   -1.5345   -0.0024   -0.0020   -0.0019    1.9565
 Low frequencies ---   16.6689   62.3371   84.7970
</pre>


<jmol><jmolApplet>
  <title>Al2Br2Cl4 Isomer 1</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-AL2_1.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Isomer 2===
Method:B3LYP/ Al 6-31G(d,p); Cl, Br LANL2DZ

Link to [[Media:Rkw-AL2_2_1.LOG|log file]]

<pre>
Al2_2
File Name = Al2_2_1
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = Gen
Charge = 0
Spin = Singlet
E(RB3LYP) = -571.43792379 a.u.
RMS Gradient Norm = 0.00013242 a.u.
Imaginary Freq = 0
Dipole Moment = 0.0276 Debye
Point Group = C1
Job cpu time:       0 days  0 hours  0 minutes 37.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000318     0.000450     YES
 RMS     Force            0.000076     0.000300     YES
 Maximum Displacement     0.000554     0.001800     YES
 RMS     Displacement     0.000243     0.001200     YES
</pre>

<pre>
Low frequencies ---   -3.7118   -2.2032   -0.0006    0.0009    0.0015    2.2873
 Low frequencies ---   18.7371   47.6135   71.2551
</pre>


<jmol><jmolApplet>
  <title>Al2Br2Cl4 Isomer 2</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-AL2_2_1.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Relative Energy===

-571.43792379 a.u.--571.43283094 a.u. = -0.00509 a.u. = -13.4 kJmol<sup>-1</sup>

Isomer 2 is lower in energy. This is because the large bromine atoms are not the bridging species, and are not forced into close proximity causing steric clashes.

===AlBrCl<sub>2</sub>===
Method:B3LYP/ Al 6-31G(d,p); Cl, Br LANL2DZ

Link to [[Media:Rkw-AL.LOG|log file]]

<pre>
Al
File Name = Al
File Type = .log
Calculation Type = FREQ
Calculation Method = RB3LYP
Basis Set = Gen
Charge = 0
Spin = Singlet
E(RB3LYP) = -285.70300759 a.u.
RMS Gradient Norm = 0.00005532 a.u.
Imaginary Freq = 0
Dipole Moment = 0.3536 Debye
Point Group = CS
Job cpu time:       0 days  0 hours  0 minutes 23.0 seconds.
</pre>

<pre>
Item               Value     Threshold  Converged?
 Maximum Force            0.000104     0.000450     YES
 RMS     Force            0.000063     0.000300     YES
 Maximum Displacement     0.000729     0.001800     YES
 RMS     Displacement     0.000610     0.001200     YES
</pre>

<pre>
Low frequencies ---   -0.0024   -0.0024   -0.0020    1.8269    2.9309    4.9652
 Low frequencies ---  119.7790  132.7679  182.5577 
</pre>

<jmol><jmolApplet>
  <title>AlBrCl2</title>
  <color>black</color>
  <size>200</size>
  <uploadedFileContents>Rkw-AL.LOG</uploadedFileContents>
</jmolApplet></jmol>

===Dissociation Energy===
ΔE = E(Al<sub>2</sub>Br<sub>2</sub>Cl<sub>4</sub>) - 2 x E(AlBrCl<sub>2</sub>) = -571.43792379 a.u. -2 x -285.70300759 a.u. = 0.03191 a.u. = -83.8 kJmol<sup>-1</sup>

The monomer is more stable than the dimer.



[[File:Rkw-Capture.PNG|PNG]]


[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 18:07, 8 May 2019 (BST) 3x MOs were required. 

[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 18:07, 8 May 2019 (BST) The LCAO decomposition for your first MO is incorrect; the terminal chlorine/bromine atoms should interact via their s orbitals.

[[User:Ng611|Ng611]] ([[User talk:Ng611|talk]]) 18:11, 8 May 2019 (BST) Second MO decomposition is good, well done.