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

using model chemistry: mPW1PW91/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at mPW1PW91/3-21G*
 hartrees
Energy at 0K-224.866941
Energy at 298.15K-224.872840
HF Energy-224.866941
Nuclear repulsion energy158.784157
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 mPW1PW91/3-21G*
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' 3302 3136 7.36      
2 A' 3267 3103 3.72      
3 A' 3104 2947 0.31      
4 A' 1596 1516 26.26      
5 A' 1519 1443 7.57      
6 A' 1445 1373 23.51      
7 A' 1310 1244 16.79      
8 A' 1295 1230 3.47      
9 A' 1252 1189 16.81      
10 A' 999 949 51.61      
11 A' 955 907 1.02      
12 A' 918 872 4.29      
13 A' 864 820 15.01      
14 A' 836 794 11.89      
15 A" 3151 2992 0.03      
16 A" 1187 1127 0.05      
17 A" 1015 964 22.69      
18 A" 979 930 1.45      
19 A" 773 734 13.79      
20 A" 582 553 20.92      
21 A" 377 358 14.26      

Unscaled Zero Point Vibrational Energy (zpe) 15363.6 cm-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 14589.3 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 mPW1PW91/3-21G*
ABC
0.31092 0.28708 0.15362

See section I.F.4 to change rotational constant units
Geometric Data calculated at mPW1PW91/3-21G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.214 0.345 0.000
C2 0.000 1.162 0.000
N3 1.123 0.526 0.000
C4 0.743 -0.920 0.000
C5 -0.768 -0.874 0.000
H6 -0.095 2.235 0.000
H7 1.155 -1.404 0.891
H8 1.155 -1.404 -0.891
H9 -1.421 -1.734 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 H6 H7 H8 H9
N11.46342.34372.32981.29832.19613.07683.07682.0895
C21.46341.29022.21022.17621.07712.95172.95173.2261
N32.34371.29021.49502.35282.09842.12602.12603.4030
C42.32982.21021.49501.51133.26401.09491.09492.3121
C51.29832.17622.35281.51133.18102.18502.18501.0799
H62.19611.07712.09843.26403.18103.94953.94954.1846
H73.07682.95172.12601.09492.18503.94951.78222.7463
H83.07682.95172.12601.09492.18503.94951.78222.7463
H92.08953.22613.40302.31211.07994.18462.74632.7463

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 116.536 N1 C2 H6 118.856
N1 C5 C4 111.820 N1 C5 H9 122.688
C2 N1 C5 103.843 C2 N3 C4 104.799
N3 C2 H6 124.608 N3 C4 C5 103.002
N3 C4 H7 109.377 N3 C4 H8 109.377
C4 C5 H9 125.493 C5 C4 H7 112.964
C5 C4 H8 112.964 H7 C4 H8 108.950
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.453      
2 C 0.161      
3 N -0.431      
4 C -0.395      
5 C 0.027      
6 H 0.265      
7 H 0.286      
8 H 0.286      
9 H 0.252      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.199 -2.160 0.000 2.170
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -35.261 -0.773 0.000
y -0.773 -23.312 0.000
z 0.000 0.000 -29.035
Traceless
 xyz
x -9.088 -0.773 0.000
y -0.773 8.836 0.000
z 0.000 0.000 0.252
Polar
3z2-r20.504
x2-y2-11.949
xy-0.773
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 5.479 -0.390 0.000
y -0.390 6.824 0.000
z 0.000 0.000 2.971


<r2> (average value of r2) Å2
<r2> 82.991
(<r2>)1/2 9.110