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

using model chemistry: QCISD/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 QCISD/6-31G(2df,p)
 hartrees
Energy at 0K-225.674126
Energy at 298.15K-225.680085
HF Energy-224.818668
Nuclear repulsion energy160.551311
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 QCISD/6-31G(2df,p)
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 A' 3266 3094 10.21      
2 A' 3245 3074 6.44      
3 A' 3097 2935 2.37      
4 A' 1684 1595 40.39      
5 A' 1598 1514 12.11      
6 A' 1451 1374 11.44      
7 A' 1348 1277 25.04      
8 A' 1332 1262 8.39      
9 A' 1293 1225 4.19      
10 A' 1050 995 55.80      
11 A' 1021 967 10.89      
12 A' 959 908 2.43      
13 A' 889 843 4.04      
14 A' 882 835 13.49      
15 A" 3141 2976 1.48      
16 A" 1188 1126 0.43      
17 A" 1029 975 11.00      
18 A" 984 932 0.80      
19 A" 775 734 3.75      
20 A" 565 535 22.65      
21 A" 373 353 5.15      

Unscaled Zero Point Vibrational Energy (zpe) 15584.3 cm-1
Scaled (by 0.9474) Zero Point Vibrational Energy (zpe) 14764.5 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 QCISD/6-31G(2df,p)
ABC
0.32080 0.29171 0.15725

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.205 0.355 0.000
C2 0.000 1.134 0.000
N3 1.118 0.508 0.000
C4 0.737 -0.902 0.000
C5 -0.765 -0.854 0.000
H6 -0.077 2.214 0.000
H7 1.143 -1.408 0.882
H8 1.143 -1.408 -0.882
H9 -1.430 -1.711 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 H6 H7 H8 H9
N11.43492.32722.31301.28632.17443.06513.06512.0777
C21.43491.28092.16542.13101.08252.92362.92363.1843
N32.32721.28091.46032.32442.08262.10982.10983.3784
C42.31302.16541.46031.50363.22051.09491.09492.3134
C51.28632.13102.32441.50363.14472.17392.17391.0839
H62.17441.08252.08263.22053.14473.92253.92254.1514
H73.06512.92362.10981.09492.17393.92251.76422.7363
H83.06512.92362.10981.09492.17393.92251.76422.7363
H92.07773.18433.37842.31341.08394.15142.73632.7363

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 117.831 N1 C2 H6 118.817
N1 C5 C4 111.764 N1 C5 H9 122.237
C2 N1 C5 102.951 C2 N3 C4 104.169
N3 C2 H6 123.352 N3 C4 C5 103.285
N3 C4 H7 110.503 N3 C4 H8 110.503
C4 C5 H9 125.999 C5 C4 H7 112.612
C5 C4 H8 112.612 H7 C4 H8 107.346
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability