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IV.C.1. (XIII.D.1.)

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyrazine)

LSDA/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3074 19 Ag 3055  
2 Ag 1511 -69 Ag 1580  
3 Ag 1220 -13 Ag 1233  
4 Ag 1012 -4 Ag 1016  
5 Ag 600 -2 Ag 602  
6 Au 997 37 Au 960  
7 Au 279 -71 Au 350  
8 B1g 926 -1 B1g 927  
9 B1u 3050 38 B1u 3012  
10 B1u 1440 -43 B1u 1483  
11 B1u 1134 4 B1u 1130  
12 B1u 978 -40 B1u 1018  
13 B2g 1001 18 B2g 983  
14 B2g 784 28 B2g 756  
15 B2u 3063 -6 B2u 3069  
16 B2u 1391 -20 B2u 1411  
17 B2u 1226 77 B2u 1149  
18 B2u 1055 -8 B2u 1063  
19 B3g 3046 6 B3g 3040  
20 B3g 1493 -32 B3g 1525  
21 B3g 1337 -9 B3g 1346  
22 B3g 708 4 B3g 704  
23 B3u 785 0 B3u 785  
24 B3u 426 8 B3u 418  
The calculated vibrational frequencies were scaled by 0.9836

See section XIII.C.3 List or set vibrational scaling factors to change the scale factors used here.
See section III.B.3.c Calculate a vibrational scaling factor for a set of molecules to determine the least squares best scaling factor.
See section III.B.3.b List of vibrational scaling factors and their uncertainties for information on where the above scaling factor is from.