Ibarramyes

lab marking

You have a good working wiki. It would be good if you round off reported values to correct significant figures and report values of wavenumber in your answers as well. If you have any specific questions, do email Prof. Hunt

NH₃ Molecule

calculation data

Name of submitted log file	NH3_OPTF_POP_MI_CHEM307.LOG
Molecule	NH3
Method	RB3LYP
Basis set	6-31G(d,p)
Final energy	-56.557769
RMS gradient	1.53e-07
Point group	C3v

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

Optimized molecule image

Jmol rotatable molecule

logfile: Media:NH3_OPTF_POP_MI_CHEM307.LOG

Optimized NH molecule

Important geometric parameters

Optimized bond distance and angle for NH₃
r(N-H)=1.018Â
θ (H-N-H)=106°

Logfile Information

 
Low frequencies ---   -5.6864   -3.6131   -3.6124   -0.0014    0.0045    0.0162
 Low frequencies --- 1089.3674 1693.9284 1693.9284

Mode	1	2	3	4	5	6
wavenumber(cm-1)	1089	1693	1693	3461	3589	3589
Symmetry	A1	E	E	A1	E	E
intensity(arbitrary units)	145	14	14	1	0.3	0.3

IR Spectrum of NH₃

Charge Analysis of NH₃

Atom	charge
N	0.375
H	-1.125

N₂F₂ Molecule

Calculation Data

Name of submitted log file	MI_N2F2_OPTF_POP_CHEM307.LOG
Molecule	N2F2
Method	RB3LYP
Basis set	6-31G(d,p)
Final energy	-309.01241
RMS gradient	3.17e-07
Point group	C2v

Item Table and Low Frequencies

         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 ---    0.0005    0.0005    0.0013    3.2233    4.3533    5.0998
 Low frequencies ---  347.8772  561.2472  771.6105

Optimized molecule image

Jmol rotatable molecule

logfile: Media:MI_N2F2_OPTF_POP_CHEM307.LOG

Optimized NF molecule

Important geometric parameters

Optimized bond distance and angle for N₂F₂
r(N-F)=1.391Â
r(N=N)1.220Â
θ (F-N=N)=35°

Logfile Information

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)	0.6	0	75	75	81	21

IR Spectrum of N₂F₂

Charge Analysis of N₂F₂

Atom	charge
N	0.215
F	-0.215

Molecular Orbitals

Additional Questions about N₂F₂

Q. How many vibrations are expected from the 3N-6 rule?
A. N₂F₂ has 4 atoms, therefore 3(4)-6=6; so 6 vibrations are expected.

Q. Why are there only 4 peaks in the IR spectrum?
A. There are 6 vibrational modes but due to its symmetry, some modes have 0 intensity. Only the modes that can change the dipole moment will appear visible on the IR spectrum.

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

Q. What is the nature of the highest energy vibration
A. The N=N stretch

Q. Which MOs are core orbital MOs?
A. MO 1 and MO 2 are for the S orbitals for the F, and MO 3 and MO 4 for the S orbitals for the N

BH₃ Molecule

calculation data

Name of submitted log file	NH3_OPTF_POP_MI_CHEM307.LOG
Molecule	BH3
Method	RB3LYP
Basis set	6-31G(d,p)
Final energy	-26.615324
RMS gradient	0.000002
Point group	D3H

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


            1                      2                      3
                     A2"                    ?A                     ?A
 Frequencies --   1162.9745              1213.1390              1213.1392
 Red. masses --      1.2531                 1.1072                 1.1072
 Frc consts  --      0.9986                 0.9600                 0.9600
 IR Inten    --     92.5682                14.0550                14.0544
  Atom  AN      X      Y      Z        X      Y      Z        X      Y      Z
     1   5     0.00   0.00  -0.16    -0.10   0.00   0.00     0.00  -0.10   0.00
     2   1     0.00   0.00   0.57     0.81   0.00   0.00     0.00  -0.08   0.00
     3   1     0.00   0.00   0.57     0.14  -0.39   0.00    -0.39   0.59   0.00
     4   1     0.00   0.00   0.57     0.14   0.39   0.00     0.39   0.59   0.00
                      4                      5                      6
                     ?B                     ?A                     ?A
 Frequencies --   2582.5813              2715.7180              2715.7189
 Red. masses --      1.0078                 1.1273                 1.1273
 Frc consts  --      3.9604                 4.8987                 4.8987
 IR Inten    --      0.0000               126.3320               126.3260
  Atom  AN      X      Y      Z        X      Y      Z        X      Y      Z
     1   5     0.00   0.00   0.00    -0.11   0.00   0.00     0.00  -0.11   0.00
     2   1     0.00   0.58   0.00    -0.02   0.00   0.00     0.00   0.81   0.00
     3   1    -0.50  -0.29   0.00     0.60   0.36   0.00     0.36   0.19   0.00
     4   1     0.50  -0.29   0.00     0.60  -0.36   0.00    -0.36   0.19   0.00