return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C4H4N2 (Pyrazine)

using model chemistry: B3PW91/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D2H 1Ag
Energy calculated at B3PW91/6-31G*
 hartrees
Energy at 0K-264.213622
Energy at 298.15K-264.219495
Nuclear repulsion energy208.801534
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 B3PW91/6-31G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Ag 3207 3068 0.00      
2 Ag 1646 1575 0.00      
3 Ag 1267 1212 0.00      
4 Ag 1055 1009 0.00      
5 Ag 604 578 0.00      
6 Au 995 952 0.00      
7 Au 345 330 0.00      
8 B1g 947 906 0.00      
9 B1u 3185 3047 9.49      
10 B1u 1533 1467 1.46      
11 B1u 1178 1127 6.52      
12 B1u 1032 987 35.22      
13 B2g 987 944 0.00      
14 B2g 777 743 0.00      
15 B2u 3200 3062 74.98      
16 B2u 1459 1396 33.20      
17 B2u 1272 1217 2.16      
18 B2u 1104 1056 10.42      
19 B3g 3185 3047 0.00      
20 B3g 1613 1543 0.00      
21 B3g 1384 1324 0.00      
22 B3g 721 690 0.00      
23 B3u 804 769 23.59      
24 B3u 431 412 21.84      

Unscaled Zero Point Vibrational Energy (zpe) 16964.8 cm-1
Scaled (by 0.9567) Zero Point Vibrational Energy (zpe) 16230.2 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 B3PW91/6-31G*
ABC
0.21467 0.19785 0.10296

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3PW91/6-31G*

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 1.408
N2 0.000 0.000 -1.408
C3 0.000 1.130 0.698
C4 0.000 -1.130 0.698
C5 0.000 -1.130 -0.698
C6 0.000 1.130 -0.698
H7 0.000 2.065 1.257
H8 0.000 -2.065 1.257
H9 0.000 -2.065 -1.257
H10 0.000 2.065 -1.257

Atom - Atom Distances (Å)
  N1 N2 C3 C4 C5 C6 H7 H8 H9 H10
N12.81501.33501.33502.38942.38942.07022.07023.37063.3706
N22.81502.38942.38941.33501.33503.37063.37062.07022.0702
C31.33502.38942.26102.65671.39501.08883.24373.74542.1660
C41.33502.38942.26101.39502.65673.24371.08882.16603.7454
C52.38941.33502.65671.39502.26103.74542.16601.08883.2437
C62.38941.33501.39502.65672.26102.16603.74543.24371.0888
H72.07023.37061.08883.24373.74542.16604.12944.83422.5134
H82.07023.37063.24371.08882.16603.74544.12942.51344.8342
H93.37062.07023.74542.16601.08883.24374.83422.51344.1294
H103.37062.07022.16603.74543.24371.08882.51344.83424.1294

picture of Pyrazine state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C3 C6 122.131 N1 C3 H7 116.966
N1 C4 C5 122.131 N1 C4 H8 116.966
N2 C5 C4 122.131 N2 C5 H9 116.966
N2 C6 C3 122.131 N2 C6 H10 116.966
C3 N1 C4 115.738 C3 C6 H10 120.903
C4 C5 H9 120.903 C5 N2 C6 115.738
C5 C4 H8 120.903 C6 C3 H7 120.903
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3PW91/6-31G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.386     -0.421
2 N -0.386     -0.421
3 C 0.010     0.158
4 C 0.010     0.158
5 C 0.010     0.158
6 C 0.010     0.158
7 H 0.183     0.053
8 H 0.183     0.053
9 H 0.183     0.053
10 H 0.183     0.053


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 0.000 0.000 0.000 0.000


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -35.228 0.000 0.000
y 0.000 -26.310 0.000
z 0.000 0.000 -40.169
Traceless
 xyz
x -1.988 0.000 0.000
y 0.000 11.388 0.000
z 0.000 0.000 -9.400
Polar
3z2-r2-18.801
x2-y2-8.917
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> 114.628
(<r2>)1/2 10.706