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

using model chemistry: G4

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at G4
 hartrees
Energy at 0K-226.075388
Energy at 298.15K-226.070590
HF Energy-226.205016
Nuclear repulsion energy160.682703
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 B3LYP/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' 3211 3099 13.68      
2 A' 3192 3080 9.67      
3 A' 3035 2929 2.17      
4 A' 1657 1599 44.11      
5 A' 1558 1504 11.24      
6 A' 1400 1351 17.55      
7 A' 1324 1278 25.30      
8 A' 1304 1258 4.46      
9 A' 1258 1214 7.55      
10 A' 1036 1000 57.31      
11 A' 996 961 11.02      
12 A' 938 905 4.15      
13 A' 882 851 2.50      
14 A' 879 848 14.85      
15 A" 3066 2959 1.43      
16 A" 1157 1117 0.43      
17 A" 1008 973 8.99      
18 A" 969 935 1.55      
19 A" 753 727 4.13      
20 A" 568 548 20.14      
21 A" 374 361 6.36      

Unscaled Zero Point Vibrational Energy (zpe) 15282.5 cm-1
Scaled (by 0.965) Zero Point Vibrational Energy (zpe) 14747.6 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 B3LYP/6-31G(2df,p)
ABC
0.32079 0.29296 0.15758

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/6-31G(2df,p)

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.199 0.357 0.000
C2 0.000 1.135 0.000
N3 1.117 0.506 0.000
C4 0.733 -0.900 0.000
C5 -0.767 -0.855 0.000
H6 -0.077 2.217 0.000
H7 1.143 -1.415 0.879
H8 1.143 -1.415 -0.879
H9 -1.435 -1.711 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 H6 H7 H8 H9
N11.42882.32022.30511.28642.17153.06553.06552.0813
C21.42881.28142.16292.13211.08462.92942.92943.1867
N32.32021.28141.45772.32402.08562.11332.11333.3802
C42.30512.16291.45771.50113.22021.09821.09822.3148
C51.28642.13212.32401.50113.14782.17602.17601.0857
H62.17151.08462.08563.22023.14783.93073.93074.1554
H73.06552.92942.11331.09822.17603.93071.75832.7395
H83.06552.92942.11331.09822.17603.93071.75832.7395
H92.08133.18673.38022.31481.08574.15542.73952.7395

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 117.313 N1 C2 H6 118.875
N1 C5 C4 111.198 N1 C5 H9 122.855
C2 N1 C5 103.671 C2 N3 C4 104.586
N3 C2 H6 123.813 N3 C4 C5 103.232
N3 C4 H7 110.810 N3 C4 H8 110.810
C4 C5 H9 125.947 C5 C4 H7 112.652
C5 C4 H8 112.652 H7 C4 H8 106.759
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/6-31G(2df,p) Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.200      
2 C 0.055      
3 N -0.200      
4 C -0.231      
5 C 0.011      
6 H 0.131      
7 H 0.152      
8 H 0.152      
9 H 0.129      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.014 -1.958 0.000 1.958
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å


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


<r2> (average value of r2) Å2
<r2> 81.297
(<r2>)1/2 9.016