Birdjo

Trimethylammonium Chloride

Calculation Data

name of submitted log file	BH3 Opt.log
molecule	C3H10NCl
method	RB3LYP
basis set	3-21G
final energy	-632.16208
RMS gradient	6.133e-06
point group	C1

Convergence Data

Item Table

         Item               Value     Threshold  Converged?
 Maximum Force            0.000017     0.000450     YES
 RMS     Force            0.000007     0.000300     YES
 Maximum Displacement     0.002004     0.001800     NO 
 RMS     Displacement     0.000651     0.001200     YES

=Low Frequencies

 Low frequencies ---   -5.4821   -2.3017   -0.0033   -0.0020    0.0020    7.2673
 Low frequencies ---   55.7661   56.4186  189.8351

Optimised C₃H₁₀NCl LOG file

File:TRIMETHYLAMMONIUM CHLORIDE OPT.LOG

Optimised C₃H₁₀NCl Molecule

Jmol Rotatable Molecule

Optimised CHNCl Molecule

BH₃ Molecule

Calculation Data

name of submitted log file	BH3 Opt.log
molecule	BH3
method	RB3LYP
basis set	6-31G(d,p)
final energy	-26.615324
RMS gradient	2.114e-06
point group	D3H

Convergence Data

Item Table

         Item               Value     Threshold  Converged?
 Maximum Force            0.000004     0.000015     YES
 RMS     Force            0.000003     0.000010     YES
 Maximum Displacement     0.000017     0.000060     YES
 RMS     Displacement     0.000011     0.000040     YES

Low Frequencies

 Low frequencies ---  -11.6940  -11.6861   -6.5543    0.0007    0.0280    0.4289
 Low frequencies --- 1162.9745 1213.1390 1213.1392

Optimised BH₃ Log File

Media:BH3_OPT.LOG

Important Geometric Parameters

r(B-H)=1.19Â
θ (H-B-H)= 120°

Optimised BH₃ Molecule

Jmol Rotatable Molecule

Optimised BH Molecule

Infrared Info

Mode	1	2	3	4	5	6
Wavenumber(cm-1)	1163	1213	1213	2583	2716	2716
Symmetry	A2	E	E	A1	E	E
Intensity (arbitrary units)	93	14	14	0	126	126

Infrared Spectrum

NH₃BH₃ Molecule

name of submitted log file	NH3BH3 opt2.log
molecule	NH3BH3
method	RB3LYP
basis set	6-31G(d,p)
final energy	-83.224689
RMS gradient	1.162e-06
point group	C3V

Convergence Data

         Item               Value     Threshold  Converged?
 Maximum Force            0.000002     0.000015     YES
 RMS     Force            0.000001     0.000010     YES
 Maximum Displacement     0.000017     0.000060     YES
 RMS     Displacement     0.000008     0.000040     YES

Low Frequencies

Low frequencies ---   -5.4185   -0.3223   -0.0475    0.0010    1.1367    1.2199
 Low frequencies ---  263.2927  632.9711  638.4651

Important Geometric Parameters

r(B-N)=1.67Â
r(B-H)=1.21Â
r(N-H)=1.02Â
θ (H-B-H)= 114° θ (H-N-H)= 108°

Optimised NH₃BH₃

Jmol Rotatable Molecule

Optimised NHBH Molecule

NH₃BH₃ Log File

Media:NH3BH3_OPT2.LOG

Energies

E(NH₃)= -26.615324 au E(BH₃)= -56.557769 au E(NH₃BH₃)= -83.224689 au

Association Energy of NH₃BH₃

E= -0.051596 au E= -136 kJ/mol

Lab marking

You have a good working wiki. It would be good if you present your work more neatly and clearly. Overall, a good attempt. If you have any specific question, do email Prof. Hunt

NH₃ molecule

Calculation Data

name of submitted log file	JSDB_NH3OPT-POP.log
molecule	NH3
method	RB3LYP
basis set	6-31G(d,p)
final energy	-56.557769
RMS gradient	1.53e-07
point group	C3v

Convergence Data

Item Table

        Item               Value     Threshold  Converged?
 Maximum Force            0.000000     0.000015     YES
 RMS     Force            0.000000     0.000010     YES
 Maximum Displacement     0.000003     0.000060     YES
 RMS     Displacement     0.000001     0.000040     YES

Low Frequencies

 Low frequencies ---   -5.6864   -3.6131   -3.6124    0.0017    0.0048    0.0162
 Low frequencies --- 1089.3674 1693.9284 1693.9284

Optimised NH₃ Log File

Media:JSDB NH3OPT-POP.LOG

Optimised NH₃ Molecule

Important Geometric Parameters

r(N-H)=1.02Â
θ (H-N-H)= 106°

Infrared Information

Mode	1	2	3	4	5	6
Wavenumber(cm-1)	1089	1694	1694	3461	3590	3590
Symmetry	A1	E	E	A1	E	E
Intensity (arbitrary units)	145	14	14	1	0	0

Charge Distribution Data

Atom	N	H
Charge	-1.13	0.38

Cis N₂F₂ molecule

Calculation Data

name of submitted log file	birdjo_n2f2opt_pop.log
molecule	N2F2
method	RB3LYP
basis set	6-31G(d,p)
final energy	-309.01241
RMS gradient	3.17e-07
point group	C2V

Convergence Data

Item Table

         Item               Value     Threshold  Converged?
 Maximum Force            0.000001     0.000015     YES
 RMS     Force            0.000000     0.000010     YES
 Maximum Displacement     0.000001     0.000060     YES
 RMS     Displacement     0.000001     0.000040     YES

Low Frequencies

Low frequencies ---    0.0016    0.0018    0.0018    3.2233    4.3533    5.0998
 Low frequencies ---  347.8772  561.2472  771.6105

Optimised N₂F₂ Log File

Media:BIRDJO_N2F2OPT_POP.LOG

Optimised N₂F₂ Molecule

Why are there no bonds?

The reason there appears to be no bonds present is because Gaussview only represents bonds within a certain distance parameter. So the N-F bonds are in fact present; they are just not represented on the programme as they are outside this parameter.

Important Geometric Parameters

r(N-F)=1.22Â
r(N-F)=1.39Â
θ (F-N-N)=114°
θ (F-N-N-F)=0°

Infrared Information

Low frequencies ---    0.0016    0.0018    0.0018    3.2233    4.3533    5.0998
 Low frequencies ---  347.8772  561.2472  771.6105

Mode	1	2	3	4	5	6
Wavenumber(cm-1)	348	561	772	949	987	1637
Symmetry	A1	A2	B2	A1	B2	A1
Intensity (arbitrary units)	1	0	75	75	81	21

Based on the 3N-6 rule we would expect to see 6 vibrational modes, so why do we only see 4 on the IR spectrum? Because mode 1 at 348cm^-1 and mode 2 at 561cm^-1 have essentially no absorption value so they are not present on the spectrum.

Which vibration is the asymmetric N-F stretch? The asymmetric N-F stretch is at 949cm^-1.

What is the nature of the highest energy vibration? It is a symmetric stretch between the two N atoms.

Charge Distribution Data

Atom	N	F
Charge	0.22	-0.22

Molecular Orbital Data

Which MOs are the core MOs?

MOs 1 and 2 are the core S orbitals for the Fluorine atoms MOs 3 and 4 are the core S orbitals for the Nitrogen atoms

MO9 Image:

LCAO Diagram of MO9