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All results from a given calculation for C3H4N2 (4H-Imidazole)

using model chemistry: PBEPBE/6-31G(2df,p)

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at PBEPBE/6-31G(2df,p)
 hartrees
Energy at 0K-225.932458
Energy at 298.15K-225.938265
HF Energy-225.932458
Nuclear repulsion energy159.895736
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at PBEPBE/6-31G(2df,p)
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3139 3107 13.08      
2 A' 3123 3091 9.56      
3 A' 2969 2938 1.03      
4 A' 1590 1574 36.90      
5 A' 1493 1478 7.53      
6 A' 1333 1319 22.70      
7 A' 1278 1265 21.75      
8 A' 1258 1245 3.97      
9 A' 1202 1190 7.97      
10 A' 1016 1006 44.95      
11 A' 977 967 15.97      
12 A' 922 912 3.99      
13 A' 858 849 8.17      
14 A' 854 845 9.54      
15 A" 3003 2972 0.23      
16 A" 1109 1098 0.38      
17 A" 961 951 9.05      
18 A" 922 913 1.98      
19 A" 716 708 5.51      
20 A" 549 543 17.26      
21 A" 356 352 7.67      

Unscaled Zero Point Vibrational Energy (zpe) 14813.0 cm-1
Scaled (by 0.9897) Zero Point Vibrational Energy (zpe) 14660.5 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at PBEPBE/6-31G(2df,p)
ABC
0.31872 0.28969 0.15617

See section I.F.4 to change rotational constant units
Geometric Data calculated at PBEPBE/6-31G(2df,p)

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.206 0.367 0.000
C2 0.000 1.136 0.000
N3 1.129 0.502 0.000
C4 0.731 -0.902 0.000
C5 -0.770 -0.857 0.000
H6 -0.070 2.227 0.000
H7 1.145 -1.426 0.882
H8 1.145 -1.426 -0.882
H9 -1.446 -1.717 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 H6 H7 H8 H9
N11.43072.33932.31531.29932.18033.08563.08562.0973
C21.43071.29482.16472.13641.09342.94162.94163.1985
N32.33931.29481.45922.33492.10062.12042.12043.3995
C42.31532.16471.45921.50093.22961.10691.10692.3246
C51.29932.13642.33491.50093.16262.18362.18361.0943
H62.18031.09342.10063.22963.16263.94963.94964.1774
H73.08562.94162.12041.10692.18363.94961.76482.7529
H83.08562.94162.12041.10692.18363.94961.76482.7529
H92.09733.19853.39952.32461.09434.17742.75292.7529

picture of 4H-Imidazole state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C2 N3 118.162 N1 C2 H6 118.881
N1 C5 C4 111.350 N1 C5 H9 122.151
C2 N1 C5 102.884 C2 N3 C4 103.467
N3 C2 H6 122.957 N3 C4 C5 104.137
N3 C4 H7 110.696 N3 C4 H8 110.696
C4 C5 H9 126.499 C5 C4 H7 112.851
C5 C4 H8 112.851 H7 C4 H8 105.726
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/6-31G(2df,p) Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.204      
2 C 0.056      
3 N -0.203      
4 C -0.254      
5 C 0.008      
6 H 0.134      
7 H 0.165      
8 H 0.165      
9 H 0.133      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.079 -1.959 0.000 1.961
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -34.105 -0.621 0.000
y -0.621 -23.868 0.000
z 0.000 0.000 -28.401
Traceless
 xyz
x -7.970 -0.621 0.000
y -0.621 7.385 0.000
z 0.000 0.000 0.585
Polar
3z2-r21.170
x2-y2-10.236
xy-0.621
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 6.512 -0.290 0.000
y -0.290 7.641 0.000
z 0.000 0.000 3.880


<r2> (average value of r2) Å2
<r2> 81.833
(<r2>)1/2 9.046