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All results from a given calculation for C4H4N2 (Pyrazine)

using model chemistry: mPW1PW91/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D2H 1Ag
Energy calculated at mPW1PW91/6-31G*
 hartrees
Energy at 0K-264.248678
Energy at 298.15K-264.254583
Nuclear repulsion energy209.177937
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 mPW1PW91/6-31G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Ag 3230 3063 0.00      
2 Ag 1663 1577 0.00      
3 Ag 1275 1209 0.00      
4 Ag 1064 1009 0.00      
5 Ag 607 576 0.00      
6 Au 1006 954 0.00      
7 Au 351 333 0.00      
8 B1g 955 906 0.00      
9 B1u 3208 3042 8.31      
10 B1u 1545 1465 1.41      
11 B1u 1186 1125 7.16      
12 B1u 1039 985 35.17      
13 B2g 996 944 0.00      
14 B2g 782 742 0.00      
15 B2u 3223 3057 69.53      
16 B2u 1469 1393 34.59      
17 B2u 1279 1213 2.88      
18 B2u 1112 1054 10.54      
19 B3g 3208 3042 0.00      
20 B3g 1631 1547 0.00      
21 B3g 1392 1320 0.00      
22 B3g 725 688 0.00      
23 B3u 811 769 24.15      
24 B3u 435 413 22.26      

Unscaled Zero Point Vibrational Energy (zpe) 17096.1 cm-1
Scaled (by 0.9483) Zero Point Vibrational Energy (zpe) 16212.2 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 mPW1PW91/6-31G*
ABC
0.21542 0.19858 0.10333

See section I.F.4 to change rotational constant units
Geometric Data calculated at mPW1PW91/6-31G*

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 1.405
N2 0.000 0.000 -1.405
C3 0.000 1.129 0.697
C4 0.000 -1.129 0.697
C5 0.000 -1.129 -0.697
C6 0.000 1.129 -0.697
H7 0.000 2.061 1.255
H8 0.000 -2.061 1.255
H9 0.000 -2.061 -1.255
H10 0.000 2.061 -1.255

Atom - Atom Distances (Å)
  N1 N2 C3 C4 C5 C6 H7 H8 H9 H10
N12.80931.33231.33232.38502.38502.06672.06673.36463.3646
N22.80932.38502.38501.33231.33233.36463.36462.06672.0667
C31.33232.38502.25702.65231.39301.08693.23823.73922.1626
C41.33232.38502.25701.39302.65233.23821.08692.16263.7392
C52.38501.33232.65231.39302.25703.73922.16261.08693.2382
C62.38501.33231.39302.65232.25702.16263.73923.23821.0869
H72.06673.36461.08693.23823.73922.16264.12244.82612.5093
H82.06673.36463.23821.08692.16263.73924.12242.50934.8261
H93.36462.06673.73922.16261.08693.23824.82612.50934.1224
H103.36462.06672.16263.73923.23821.08692.50934.82614.1224

picture of Pyrazine state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C3 C6 122.108 N1 C3 H7 116.994
N1 C4 C5 122.108 N1 C4 H8 116.994
N2 C5 C4 122.108 N2 C5 H9 116.994
N2 C6 C3 122.108 N2 C6 H10 116.994
C3 N1 C4 115.783 C3 C6 H10 120.897
C4 C5 H9 120.897 C5 N2 C6 115.783
C5 C4 H8 120.897 C6 C3 H7 120.897
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/6-31G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.392      
2 N -0.392      
3 C 0.007      
4 C 0.007      
5 C 0.007      
6 C 0.007      
7 H 0.189      
8 H 0.189      
9 H 0.189      
10 H 0.189      


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


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -35.261 0.000 0.000
y 0.000 -26.249 0.000
z 0.000 0.000 -40.170
Traceless
 xyz
x -2.051 0.000 0.000
y 0.000 11.466 0.000
z 0.000 0.000 -9.415
Polar
3z2-r2-18.830
x2-y2-9.012
xy0.000
xz0.000
yz0.000


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> 114.290
(<r2>)1/2 10.691