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

using model chemistry: HF/CEP-31G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at HF/CEP-31G
 hartrees
Energy at 0K-37.993056
Energy at 298.15K-37.999224
HF Energy-37.993056
Nuclear repulsion energy82.870850
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 HF/CEP-31G
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' 3497 3152 14.03      
2 A' 3451 3111 12.74      
3 A' 3266 2944 11.28      
4 A' 1770 1596 54.70      
5 A' 1686 1520 22.00      
6 A' 1576 1420 22.86      
7 A' 1428 1287 12.38      
8 A' 1422 1282 36.78      
9 A' 1384 1247 3.68      
10 A' 1096 988 78.35      
11 A' 1070 964 13.15      
12 A' 1010 910 2.61      
13 A' 950 856 3.05      
14 A' 941 848 16.79      
15 A" 3320 2993 16.77      
16 A" 1267 1142 0.04      
17 A" 1135 1023 20.33      
18 A" 1082 975 0.00      
19 A" 861 776 9.28      
20 A" 623 561 37.39      
21 A" 422 380 9.70      

Unscaled Zero Point Vibrational Energy (zpe) 16626.9 cm-1
Scaled (by 0.9014) Zero Point Vibrational Energy (zpe) 14987.4 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 HF/CEP-31G
ABC
0.31187 0.29084 0.15481

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/CEP-31G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.200 0.351 0.000
C2 0.000 1.163 0.000
N3 1.111 0.514 0.000
C4 0.748 -0.918 0.000
C5 -0.775 -0.870 0.000
H6 -0.081 2.232 0.000
H7 1.154 -1.412 0.880
H8 1.154 -1.412 -0.880
H9 -1.439 -1.714 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 H6 H7 H8 H9
N11.44872.31612.32451.29222.18823.06893.06892.0791
C21.44871.28662.21152.17581.07162.95552.95553.2174
N32.31611.28661.47712.33932.09092.11762.11763.3864
C42.32452.21151.47711.52433.25701.08751.08752.3279
C51.29222.17582.33931.52433.17822.18842.18841.0743
H62.18821.07162.09093.25703.17823.94633.94634.1732
H73.06892.95552.11761.08752.18843.94631.76032.7549
H83.06892.95552.11761.08752.18843.94631.76032.7549
H92.07913.21743.38642.32791.07434.17322.75492.7549

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 115.590 N1 C2 H6 119.754
N1 C5 C4 110.974 N1 C5 H9 122.669
C2 N1 C5 104.941 C2 N3 C4 106.094
N3 C2 H6 124.656 N3 C4 C5 102.401
N3 C4 H7 110.395 N3 C4 H8 110.395
C4 C5 H9 126.357 C5 C4 H7 112.768
C5 C4 H8 112.768 H7 C4 H8 108.053
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N 0.033      
2 C -0.382      
3 N 0.020      
4 C -0.189      
5 C -0.317      
6 H 0.243      
7 H 0.171      
8 H 0.171      
9 H 0.250      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  -0.020 -2.609 0.000 2.609
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -38.200 -0.703 0.000
y -0.703 -23.463 0.000
z 0.000 0.000 -29.444
Traceless
 xyz
x -11.746 -0.703 0.000
y -0.703 10.359 0.000
z 0.000 0.000 1.387
Polar
3z2-r22.774
x2-y2-14.737
xy-0.703
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 5.895 -0.549 0.000
y -0.549 6.947 0.000
z 0.000 0.000 3.430


<r2> (average value of r2) Å2
<r2> 68.913
(<r2>)1/2 8.301