ChemWiki - User contributions [en]

Zcj17y2comp

2019-05-10T16:18:36Z

Zcj17:

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[Image:Zcj17BH3 2 sym opt631g dp.PNG|thumb|center|BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

{| class="wikitable"
|-
! Wavenumber (cm-1)
! Intensity (arbitrary)
! Symmetry
! IR Active?
! Type
|-
| 1163
| 92.6
| A''2
| Yes
| Out-of-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 2582
| 0
| A'1
| No
| Totally symmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|}

'''IR Spectrum'''
[[image:ZCJIR Spectrum.PNG|center|BH3 IR Spectrum]]

'''JMol'''
<jmol><jmolApplet>
<title> optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[image:ZCJ17Completed annotated MO diagram.PNG|centre|BH3 MO Diagram]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[image:ZCJNH3 3 sym opt631g dp.PNG|thumb|centre|NH3 Symmetry Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===NH3BH3===

'''B3LYP/6-61G level'''

[[image:ZCJNH3BH table.PNG|thumb|centre|NH3BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 347 kJ/mol (from http://butane.chem.uiuc.edu/cyerkes/Chem104ACSpring2009/Genchemref/bondenergies.html|date accessed 10/05/19), which is about 2.5 times the strength.

===NI3===

'''B3LYP/6-61G level'''

[[image:ZCJ NI3 opt.PNG|thumb|centre|NI3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[NI3|https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ NCH3 opt.PNG|thumb|centre|N(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES
</pre>

Frequency analysis log file:[[File:N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ PCH3 opt.PNG|thumb|centre|P(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! Electronegativity (from http://www.rsc.org/periodic-table/trends)
|-
| Phosphorous
| 2.19
|-
| Nitrogen
| 3.04
|-
| Carbon
| 2.55
|}

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the nitrogen cation, the positive charge is shared between the nitrogen and the carbons. In the phosphorous cation, the charge is more localised to the phosophorous atom, however in all cases, charge is spread around the molecule to a certain extent
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

====MOs====

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNG|thumb|center|Real MO6]]

This MO is totally bonding. It is constructed from the 1s hydrogen orbitals and the 2s carbon and nitrogen oribitals all constructively overlapping

[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

This MO is also totally bonding. It is constructed from the 1s hydrogen orgitals overlapping constructively with a carbon 2s orbital. These ligands then overlap constructively witht he nitrogen 2p orbitals, 2 as is, and 2 with inverted phase.

[[Image:ZCJLAST MO.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

This is also a bonding orbital, with some antibonding charactetr through space. It is constructed from the hydrogen 1s orbitals overlapping in phase witht the carbon 2p orbital which is is then overlapping in phase again with the nitrogen 2p orbital for each ligand.

Zcj17y2comp

2019-05-10T16:17:11Z

Zcj17: /* Charges */

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[Image:Zcj17BH3 2 sym opt631g dp.PNG|thumb|center|BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

{| class="wikitable"
|-
! Wavenumber (cm-1)
! Intensity (arbitrary)
! Symmetry
! IR Active?
! Type
|-
| 1163
| 92.6
| A''2
| Yes
| Out-of-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 2582
| 0
| A'1
| No
| Totally symmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|}

'''IR Spectrum'''
[[image:ZCJIR Spectrum.PNG|center|BH3 IR Spectrum]]

'''JMol'''
<jmol><jmolApplet>
<title> optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[image:ZCJ17Completed annotated MO diagram.PNG|centre|BH3 MO Diagram]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[image:ZCJNH3 3 sym opt631g dp.PNG|thumb|centre|NH3 Symmetry Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===NH3BH3===

'''B3LYP/6-61G level'''

[[image:ZCJNH3BH table.PNG|thumb|centre|NH3BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 347 kJ/mol (from http://butane.chem.uiuc.edu/cyerkes/Chem104ACSpring2009/Genchemref/bondenergies.html|date accessed 10/05/19), which is about 2.5 times the strength.

===NI3===

'''B3LYP/6-61G level'''

[[image:ZCJ NI3 opt.PNG|thumb|centre|NI3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ NCH3 opt.PNG|thumb|centre|N(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES
</pre>

Frequency analysis log file:[[File:N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ PCH3 opt.PNG|thumb|centre|P(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! Electronegativity (from http://www.rsc.org/periodic-table/trends)
|-
| Phosphorous
| 2.19
|-
| Nitrogen
| 3.04
|-
| Carbon
| 2.55
|}

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the nitrogen cation, the positive charge is shared between the nitrogen and the carbons. In the phosphorous cation, the charge is more localised to the phosophorous atom, however in all cases, charge is spread around the molecule to a certain extent
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

====MOs====

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNG|thumb|center|Real MO6]]

This MO is totally bonding. It is constructed from the 1s hydrogen orbitals and the 2s carbon and nitrogen oribitals all constructively overlapping

[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

This MO is also totally bonding. It is constructed from the 1s hydrogen orgitals overlapping constructively with a carbon 2s orbital. These ligands then overlap constructively witht he nitrogen 2p orbitals, 2 as is, and 2 with inverted phase.

[[Image:ZCJLAST MO.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

This is also a bonding orbital, with some antibonding charactetr through space. It is constructed from the hydrogen 1s orbitals overlapping in phase witht the carbon 2p orbital which is is then overlapping in phase again with the nitrogen 2p orbital for each ligand.

Zcj17y2comp

2019-05-10T16:15:24Z

Zcj17: /* MOs */

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[Image:Zcj17BH3 2 sym opt631g dp.PNG|thumb|center|BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

{| class="wikitable"
|-
! Wavenumber (cm-1)
! Intensity (arbitrary)
! Symmetry
! IR Active?
! Type
|-
| 1163
| 92.6
| A''2
| Yes
| Out-of-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 2582
| 0
| A'1
| No
| Totally symmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|}

'''IR Spectrum'''
[[image:ZCJIR Spectrum.PNG|center|BH3 IR Spectrum]]

'''JMol'''
<jmol><jmolApplet>
<title> optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[image:ZCJ17Completed annotated MO diagram.PNG|centre|BH3 MO Diagram]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[image:ZCJNH3 3 sym opt631g dp.PNG|thumb|centre|NH3 Symmetry Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===NH3BH3===

'''B3LYP/6-61G level'''

[[image:ZCJNH3BH table.PNG|thumb|centre|NH3BH3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 347 kJ/mol (from http://butane.chem.uiuc.edu/cyerkes/Chem104ACSpring2009/Genchemref/bondenergies.html|date accessed 10/05/19), which is about 2.5 times the strength.

===NI3===

'''B3LYP/6-61G level'''

[[image:ZCJ NI3 opt.PNG|thumb|centre|NI3 Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ NCH3 opt.PNG|thumb|centre|N(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES
</pre>

Frequency analysis log file:[[File:N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ PCH3 opt.PNG|thumb|centre|P(CH3)4+ Summary Table]]

'''Item Table'''
<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

'''Low Frequency Table'''
<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999
</pre>

'''JMol'''
<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! Electronegativity (from http://www.rsc.org/periodic-table/trends)
|-
| Phosphorous
| 2.19
|-
| Nitrogen
| 3.04
|-
| Carbon
| 2.55
|}

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the Nitrogen cation, the positive charge is shared between the nitrogen and the carbons
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

====MOs====

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNG|thumb|center|Real MO6]]

This MO is totally bonding. It is constructed from the 1s hydrogen orbitals and the 2s carbon and nitrogen oribitals all constructively overlapping

[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

This MO is also totally bonding. It is constructed from the 1s hydrogen orgitals overlapping constructively with a carbon 2s orbital. These ligands then overlap constructively witht he nitrogen 2p orbitals, 2 as is, and 2 with inverted phase.

[[Image:ZCJLAST MO.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

This is also a bonding orbital, with some antibonding charactetr through space. It is constructed from the hydrogen 1s orbitals overlapping in phase witht the carbon 2p orbital which is is then overlapping in phase again with the nitrogen 2p orbital for each ligand.

2019-05-10T15:59:05Z

Zcj17:

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[Image:Zcj17BH3 2 sym opt631g dp.PNG|thumb|center|BH3 Summary Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

{| class="wikitable"
|-
! Wavenumber (cm-1)
! Intensity (arbitrary)
! Symmetry
! IR Active?
! Type
|-
| 1163
| 92.6
| A''2
| Yes
| Out-of-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 1213
| 14.0
| E'
| Very slight
| In-plane bend
|-
| 2582
| 0
| A'1
| No
| Totally symmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|-
| 2716
| 126.3
| E'
| Yes
| Asymmetric stretch
|}

[[image:ZCJIR Spectrum.PNG|center|BH3 IR Spectrum]]

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[image:ZCJ17Completed annotated MO diagram.PNG|centre|BH3 MO Diagram]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[image:ZCJNH3 3 sym opt631g dp.PNG|thumb|centre|NH3 Symmetry Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

NH3BH3

'''B3LYP/6-61G level'''

[[image:ZCJNH3BH table.PNG|thumb|centre|NH3BH3 Summary Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 347 kJ/mol (from http://butane.chem.uiuc.edu/cyerkes/Chem104ACSpring2009/Genchemref/bondenergies.html|date accessed 10/05/19), which is about 2.5 times the strength.

===NI3===

'''B3LYP/6-61G level'''

[[image:ZCJ NI3 opt.PNG|thumb|centre|NI3 Summary Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ NCH3 opt.PNG|thumb|centre|N(CH3)4+ Summary Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES
</pre>

Frequency analysis log file:[[File:N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[image:ZCJ PCH3 opt.PNG|thumb|centre|P(CH3)4+ Summary Table]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999
</pre>

<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! Electronegativity (from http://www.rsc.org/periodic-table/trends)
|-
| Phosphorous
| 2.19
|-
| Nitrogen
| 3.04
|-
| Carbon
| 2.55
|}

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
|
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the Nitrogen cation, the positive charge is shared between the nitrogen and the carbons
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

====MOs====

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNG|thumb|center|Real MO6]]

This MO is totally bonding. It is constructed from the 1s hydrogen orbitals and the 2s carbon and nitrogen oribitals all constructively overlapping

[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

This MO is also totally bonding. It is constructed from the 1s hydrogen orgitals overlapping constructively with a carbon 2s orbital. These ligands then overlap constructively witht he nitrogen 2p orbitals, 2 as is, and 2 with inverted phase.

[[Image:ZCjMYLCAO20.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

This is also a bonding orbital, with some antibonding charactetr through space. It is constructed from the hydrogen 1s orbitals overlapping in phase witht the carbon 2p orbital which is is then overlapping in phase again with the nitrogen 2p orbital for each ligand.

2019-05-10T14:55:05Z

Zcj17:

Zcj17y2comp

2019-05-10T14:44:46Z

Zcj17: /* MOs */

a title identifying the molecule

the method and basis set defined

an image of the summary table produced by gaussview (after optimisation)

the "Item" table (in pre tags) from the *.log file (from the optimisation job)

a link to the frequency and/or population analysis files

low frequencies data (in pre tags) from the *.log file (from the frequency job)

a rotatable 3d jmol file/image of the optimised structure

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[File:Zcj17BH3 2 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES

</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[File:ZCJ17Completed annotated MO diagram.PNG]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[File:ZCJNH3 3 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

NH3BH3

'''B3LYP/6-61G level'''

[[File:ZCJNH3BH table.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 346 kJ/mol, which is about 2.5 times the strength. (R$EFERENCE)

===NI3===

'''B3LYP/6-61G level'''

[[File:ZCJ NI3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===
NCH34

Optimisation
Frequency
Compute MOS
NBO charge analysis

Visualise MOSs
Draw/compare

PCH34
Optimisation
Frequency
Compute MOS
NBO charge analysis

Compare charge distribution
Discuss and list the charges

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ NCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES

</pre>

Frequency analysis log file:[[N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ PCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999

</pre>

<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the Nitrogen cation, the positive charge is shared between the nitrogen and the carbons
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

===MOs===
[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNG|thumb|center|Real MO6]]

[[Image:ZCjMYLCAO20.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

Zcj17y2comp

2019-05-10T14:44:18Z

Zcj17: /* MOs */

a title identifying the molecule

the method and basis set defined

an image of the summary table produced by gaussview (after optimisation)

the "Item" table (in pre tags) from the *.log file (from the optimisation job)

a link to the frequency and/or population analysis files

low frequencies data (in pre tags) from the *.log file (from the frequency job)

a rotatable 3d jmol file/image of the optimised structure

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[File:Zcj17BH3 2 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES

</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[File:ZCJ17Completed annotated MO diagram.PNG]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[File:ZCJNH3 3 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

NH3BH3

'''B3LYP/6-61G level'''

[[File:ZCJNH3BH table.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 346 kJ/mol, which is about 2.5 times the strength. (R$EFERENCE)

===NI3===

'''B3LYP/6-61G level'''

[[File:ZCJ NI3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===
NCH34

Optimisation
Frequency
Compute MOS
NBO charge analysis

Visualise MOSs
Draw/compare

PCH34
Optimisation
Frequency
Compute MOS
NBO charge analysis

Compare charge distribution
Discuss and list the charges

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ NCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES

</pre>

Frequency analysis log file:[[N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ PCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999

</pre>

<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[Image:ZCJPCH3 charge.PNG|thumb|center|P(CH3)4+]]
[[Image:ZCJNCH3 charge.PNG|thumb|center|N(CH3)4+]]

{| class="wikitable"
|-
! Atom
! P(CH3)4+
! N(CH3)4+
! Notes
|-
| P/N
| 1.666
| -0.295
| rowspan=3|The phosphorous charge is positive, whereas the nitrogen's is negative. This is due to the difference in electronegativities. Nitrogen has an electronegativity of 3.04, whereas phosphorous has an electronegativity of 2.19. A low electronegativity means an atom can more easily stabilise a positive charge. In the Nitrogen cation, the positive charge is shared between the nitrogen and the carbons
|-
| Carbon
| -1.060
| -0.483
|-
| Hydrogen
| 0.298
| 0.269
|}

===MOs===
[[Image:ZcjMYLCAOMO8.PNG|thumb|left|LCAO for MO8]]
[[Image:ZCJMYMO8.PNG|thumb|center|Real MO]]

[[Image:ZcjMYLCAOMO6.PNG|thumb|left|LCAO for MO6]]
[[Image:ZcjMYMO6.PNGthumb|center|Real MO6]]

[[Image:ZCjMYLCAO20.PNG|thumb|left|LCAO for MO20]]
[[Image:ZCJ17MYMO20.PNG|thumb|center|Real MO]]

Zcj17y2comp

2019-05-10T14:43:27Z

Zcj17:

a title identifying the molecule

the method and basis set defined

an image of the summary table produced by gaussview (after optimisation)

the "Item" table (in pre tags) from the *.log file (from the optimisation job)

a link to the frequency and/or population analysis files

low frequencies data (in pre tags) from the *.log file (from the frequency job)

a rotatable 3d jmol file/image of the optimised structure

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[File:Zcj17BH3 2 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES

</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[File:ZCJ17Completed annotated MO diagram.PNG]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[File:ZCJNH3 3 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

NH3BH3

'''B3LYP/6-61G level'''

[[File:ZCJNH3BH table.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 346 kJ/mol, which is about 2.5 times the strength. (R$EFERENCE)

===NI3===

'''B3LYP/6-61G level'''

[[File:ZCJ NI3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===
NCH34

Optimisation
Frequency
Compute MOS
NBO charge analysis

Visualise MOSs
Draw/compare

PCH34
Optimisation
Frequency
Compute MOS
NBO charge analysis

Compare charge distribution
Discuss and list the charges

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ NCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES

</pre>

Frequency analysis log file:[[N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ PCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999

</pre>

<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[File:ZCJPCH3 charge.PNG|P(CH3)4+]]
[[File:ZCJNCH3 charge.PNG|N(CH3)4+]]

Zcj17y2comp

2019-05-09T13:27:26Z

Zcj17:

a title identifying the molecule

the method and basis set defined

an image of the summary table produced by gaussview (after optimisation)

the "Item" table (in pre tags) from the *.log file (from the optimisation job)

a link to the frequency and/or population analysis files

low frequencies data (in pre tags) from the *.log file (from the frequency job)

a rotatable 3d jmol file/image of the optimised structure

===EX3 Section===

====BH3====

'''B3LYP/6-61G level'''

[[File:Zcj17BH3 2 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES

</pre>

Frequency analysis log file:[[BH3|https://wiki.ch.ic.ac.uk/wiki/images/c/c2/ZCJ17_BH3_FREQ.LOG]]

<pre>
Low frequencies --- -7.5936 -1.5614 -0.0054 0.6514 6.9319 7.1055
Low frequencies --- 1162.9677 1213.1634 1213.1661
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ17_BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

===BH3 MO Diagram===

[[File:ZCJ17Completed annotated MO diagram.PNG]]

Diagram adapted from http://www.huntresearchgroup.org.uk/teaching/teaching_comp_lab_year2a/Tut_MO_diagram_BH3.pdf

====Are there any significant differences between the real and LCAO MOs?====

There are some significant differences between the MOs formed from the LCAO process and the computer-generated MOS. Firstly, The The LCAO MOs are simply superimposed atomic orbitals. This means it is not possible to see the total effect on placing two orbitals near each other. In contrast the 'real' MOS are created by fully calculating the effect of all of the different atomic or fragment orbitals involved. This means they appear more diffuse and, in some cases, less clear in precisely which orbitals are involved.

====What does this say about the accuracy and usefulness of qualitative MO theory?====

The LCAO MOs are more qualitative and therefore, are less accurate as a true picture of molecular orbitals as the computer generated MOs. This inherently makes them less useful in complex molecular analysis. However, they do have some use in identifying specifically which atomic orbitals are involved in certain bonding interactions.

===NH3BH3===

====NH3====
'''B3LYP/6-61G level'''

[[File:ZCJNH3 3 sym opt631g dp.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000009 0.000450 YES
RMS Force 0.000006 0.000300 YES
Maximum Displacement 0.000019 0.001800 YES
RMS Displacement 0.000011 0.001200 YES
</pre>

Frequency analysis log file:[[NH3|https://wiki.ch.ic.ac.uk/wiki/images/2/21/ZCJ_NH3_3_FREQ.LOG]]

<pre>
Low frequencies --- -8.5223 -8.4750 -0.0037 0.0334 0.1918 26.4067
Low frequencies --- 1089.7616 1694.1862 1694.1866
</pre>

<jmol><jmolApplet>
<title>optimised NH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ NH3 3 FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

NH3BH3

'''B3LYP/6-61G level'''

[[File:ZCJNH3BH table.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000139 0.000450 YES
RMS Force 0.000063 0.000300 YES
Maximum Displacement 0.000771 0.001800 YES
RMS Displacement 0.000338 0.001200 YES
</pre>

Frequency analysis log file:[[NH3BH3|https://wiki.ch.ic.ac.uk/wiki/images/7/72/ZCJNH3BH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0614 -0.0448 -0.0066 22.0873 22.0930 40.5268
Low frequencies --- 265.8900 632.3722 640.1154
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJNH3BH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Energies====

E(NH3)= -56.5578 a.u.

E(BH3)= -26.61532 a.u.

E(NH3BH3)= -83.2247 a.u.

ΔE=E(NH3BH3)-[E(NH3)+E(BH3)

=-83.22469 - [-56.55777 + -26.6153]
= -0.05162 a.u.
= -136 kJ/mol

The N-B bond energy is fairly weak. In comparison, a C-C single bond in ethene is 346 kJ/mol, which is about 2.5 times the strength. (R$EFERENCE)

===NI3===

'''B3LYP/6-61G level'''

[[File:ZCJ NI3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000002 0.000450 YES
RMS Force 0.000002 0.000300 YES
Maximum Displacement 0.000022 0.001800 YES
RMS Displacement 0.000014 0.001200 YES
</pre>

Frequency analysis log file:[[https://wiki.ch.ic.ac.uk/wiki/images/e/e6/ZCJ_NI3_FREQ.LOG]]

<pre>
Low frequencies --- -12.5522 -12.5460 -6.0047 -0.0040 0.0191 0.0664
Low frequencies --- 100.9969 100.9977 147.3377
</pre>

<jmol><jmolApplet>
<title>optimised BH3 molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NI3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

N-I optimised distance- 2.1840 Å

===Project Section===
NCH34

Optimisation
Frequency
Compute MOS
NBO charge analysis

Visualise MOSs
Draw/compare

PCH34
Optimisation
Frequency
Compute MOS
NBO charge analysis

Compare charge distribution
Discuss and list the charges

====N(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ NCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000073 0.000450 YES
RMS Force 0.000018 0.000300 YES
Maximum Displacement 0.000277 0.001800 YES
RMS Displacement 0.000088 0.001200 YES

</pre>

Frequency analysis log file:[[N(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/7/79/ZCJ_NCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0008 -0.0006 -0.0002 35.6259 35.6259 35.6259
Low frequencies --- 215.5175 315.1186 315.1186
</pre>

<jmol><jmolApplet>
<title>optimised N(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_NCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====P(CH3)4+====

'''B3LYP/6-61G level'''

[[File:ZCJ PCH3 opt.PNG]]

<pre>
Item Value Threshold Converged?
Maximum Force 0.000138 0.000450 YES
RMS Force 0.000035 0.000300 YES
Maximum Displacement 0.000718 0.001800 YES
RMS Displacement 0.000298 0.001200 YES
</pre>

Frequency analysis log file:[[P(CH3)4+|https://wiki.ch.ic.ac.uk/wiki/images/d/d5/ZCJ_PCH3_FREQ.LOG]]

<pre>
Low frequencies --- -0.0024 -0.0023 -0.0016 51.6355 51.6355 51.6355
Low frequencies --- 188.7455 213.5999 213.5999

</pre>

<jmol><jmolApplet>
<title>optimised P(CH3)4+ molecule</title>
<color>lightgrey</color>
<size>200</size>
<uploadedFileContents>ZCJ_PCH3_FREQ.LOG</uploadedFileContents>
</jmolApplet></jmol>

====Charges====

[[File:ZCJPCH3 charge.PNG]]
[[File:ZCJNCH3 charge.PNG]]