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All results from a given calculation for C4H4N2 (Pyrazine)

using model chemistry: BLYP/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D2H 1Ag
Energy calculated at BLYP/3-21G*
 hartrees
Energy at 0K-262.754941
Energy at 298.15K-262.760705
Nuclear repulsion energy205.398078
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 BLYP/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 Ag 3122 3102 0.00      
2 Ag 1490 1481 0.00      
3 Ag 1229 1221 0.00      
4 Ag 977 970 0.00      
5 Ag 610 606 0.00      
6 Au 996 989 0.00      
7 Au 309 307 0.00      
8 B1g 935 928 0.00      
9 B1u 3097 3076 18.26      
10 B1u 1458 1449 15.39      
11 B1u 1124 1117 0.29      
12 B1u 968 961 23.61      
13 B2g 998 991 0.00      
14 B2g 776 771 0.00      
15 B2u 3112 3091 76.49      
16 B2u 1402 1393 21.14      
17 B2u 1130 1123 2.22      
18 B2u 1032 1025 9.37      
19 B3g 3094 3074 0.00      
20 B3g 1436 1426 0.00      
21 B3g 1354 1345 0.00      
22 B3g 707 703 0.00      
23 B3u 795 790 32.03      
24 B3u 426 424 18.92      

Unscaled Zero Point Vibrational Energy (zpe) 16287.3 cm-1
Scaled (by 0.9935) Zero Point Vibrational Energy (zpe) 16181.5 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 BLYP/3-21G*
ABC
0.20547 0.19333 0.09961

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

Point Group is D2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 0.000 0.000 1.428
N2 0.000 0.000 -1.428
C3 0.000 1.158 0.702
C4 0.000 -1.158 0.702
C5 0.000 -1.158 -0.702
C6 0.000 1.158 -0.702
H7 0.000 2.095 1.262
H8 0.000 -2.095 1.262
H9 0.000 -2.095 -1.262
H10 0.000 2.095 -1.262

Atom - Atom Distances (Å)
  N1 N2 C3 C4 C5 C6 H7 H8 H9 H10
N12.85651.36681.36682.42452.42452.10182.10183.40963.4096
N22.85652.42452.42451.36681.36683.40963.40962.10182.1018
C31.36682.42452.31562.70791.40381.09183.30083.79972.1758
C41.36682.42452.31561.40382.70793.30081.09182.17583.7997
C52.42451.36682.70791.40382.31563.79972.17581.09183.3008
C62.42451.36681.40382.70792.31562.17583.79973.30081.0918
H72.10183.40961.09183.30083.79972.17584.19044.89142.5232
H82.10183.40963.30081.09182.17583.79974.19042.52324.8914
H93.40962.10183.79972.17581.09183.30084.89142.52324.1904
H103.40962.10182.17583.79973.30081.09182.52324.89144.1904

picture of Pyrazine state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C3 C6 122.103 N1 C3 H7 117.056
N1 C4 C5 122.103 N1 C4 H8 117.056
N2 C5 C4 122.103 N2 C5 H9 117.056
N2 C6 C3 122.103 N2 C6 H10 117.056
C3 N1 C4 115.794 C3 C6 H10 120.841
C4 C5 H9 120.841 C5 N2 C6 115.794
C5 C4 H8 120.841 C6 C3 H7 120.841
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at BLYP/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 N -0.450 0.000    
2 N -0.450 0.000    
3 C 0.028 0.000    
4 C 0.028 0.000    
5 C 0.028 0.000    
6 C 0.028 0.000    
7 H 0.197 0.000    
8 H 0.197 0.000    
9 H 0.197 0.000    
10 H 0.197 0.000    


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 0.000 0.000 0.000 0.000
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -35.931 0.000 0.000
y 0.000 -26.940 0.000
z 0.000 0.000 -40.961
Traceless
 xyz
x -1.980 0.000 0.000
y 0.000 11.506 0.000
z 0.000 0.000 -9.526
Polar
3z2-r2-19.052
x2-y2-8.991
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> 118.099
(<r2>)1/2 10.867