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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 3069 14 Ag 3055  
2 Ag 1509 -71 Ag 1580  
3 Ag 1218 -15 Ag 1233  
4 Ag 1010 -6 Ag 1016  
5 Ag 599 -3 Ag 602  
6 Au 996 36 Au 960  
7 Au 278 -72 Au 350  
8 B1g 924 -3 B1g 927  
9 B1u 3045 33 B1u 3012  
10 B1u 1437 -46 B1u 1483  
11 B1u 1132 2 B1u 1130  
12 B1u 976 -42 B1u 1018  
13 B2g 1000 17 B2g 983  
14 B2g 783 27 B2g 756  
15 B2u 3058 -11 B2u 3069  
16 B2u 1389 -22 B2u 1411  
17 B2u 1224 75 B2u 1149  
18 B2u 1053 -10 B2u 1063  
19 B3g 3042 2 B3g 3040  
20 B3g 1491 -34 B3g 1525  
21 B3g 1335 -11 B3g 1346  
22 B3g 706 2 B3g 704  
23 B3u 784 -1 B3u 785  
24 B3u 426 8 B3u 418  
The calculated vibrational frequencies were scaled by 0.982

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.