User:Healyquin

lab marking

You have a good working wiki. It would be good if you round off reported values to correct significant figures. Reported angle of N2F2 is incorrect and value of energy reported is in hartree not kJ/mol. Overall a good attempt. If you have any specific questions, do email Prof. Hunt

NH₃ Molecule

Calculation Data

Name of submitted log file	Media:QH_NH3_OPT.LOG
Molecule	NH3
Method	RB3LYP
Basis Set	6-31G(d,p)
Final Energy (kJ/mol)	-56.6
RMS Gradient	0.00000
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 NH₃ Molecule

Interactable NH Molecule

Important Geometric Parameters

Optimized Bond Distance for NH₃
(N-H)=1.02Â
θ(H-N-H)=105°

IR/Vibration Frequencies of NH₃

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

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

Charge Distribution: Table and Molecule

Atom	Charge
Nitrogen	-1.125
Hydrogens	0.375

Molecular Orbitals

Project Molecule

Calculation Data

Name of submitted log file	Media:QH_N2F2_OPT.LOG
Molecule	N2F2
Method	RB3LYP
Basis Set	6-31G(d,p)
Final Energy (kJ/mol)	-309
RMS Gradient	0.000001
Point Group	C2v

Item Table

        Item               Value     Threshold  Converged?
Maximum Force            0.000002     0.000015     YES
RMS     Force            0.000001     0.000010     YES
Maximum Displacement     0.000010     0.000060     YES
RMS     Displacement     0.000006     0.000040     YES

Optimized Bond Distances and Angle

(N-F)=1.39Â
(N-N)=1.22Â
θ(F-N-F)=79°
These optimized geometric parameters, confirm that the optimization of N₂F₂ took place.

Optimized N₂F₂ Molecule

There does not seem to be bonds between the N and F atoms of the optimized structure, possibly because they are too large (long) for the standard optimized bond size range to compute.

Interactable NF Molecule

IR/Vibration Frequencies and Analysis

Low frequencies ---   -0.0005    0.0015    0.0018    3.4936    4.3717    5.1617
Low frequencies ---  347.8732  561.2460  771.6039

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

There are 6 vibration modes of N₂F₂ because of 3N-6: 3(4) = 12 - 6 = 6

As mode 1 and 2 have an intensity of ~0, they can't really be seen on the IR spectra, hence why you can only see 4 peaks. The vibration of the asymmetrical N-F stretch seems to be mode 3 (772cm^-1) as both sides are stretching at different times. The highest energy vibration seems to be mode 6, where it is just the two N atoms stretching away and back towards each other (N=N stretch).

Charge Distribution: Table and Molecule

Atom	Charge	Colour
Nitrogen	0.215	Lime Green
Fluoride	-0.215	Bright Red

Fluorine is more electronegative (most electronegative element), hence why it has a greater negative charge than Nitrogen.

Molecular Orbitals

The core MOs, seem to be 1-4: 1 and 2 are the F atom core MOs. 3 and 4 are the N atom core MOs.