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Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

PBEPBE/6-31G**

18 11 26 13 55
Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency Scaled
Frequency
Harm.
diff
Fund.
diff
Symmetry Harmonic
Frequency
Fundamental
Frequency
Comment
1 A1 3145 3102   39 A1   3063  
2 A1 3115 3072   29 A1   3043  
3 A1 1572 1550   -22 A1   1572  
4 A1 1439 1420   6 A1   1414  
5 A1 1190 1174   -109 A1   1283  
6 A1 1138 1122   -38 A1   1160  
7 A1 1069 1055   -8 A1   1063  
8 A1 987 974   10 A1   964  
9 A1 659 650   31 A1   619  
10 A2 976 963   27 A2   936  
11 A2 910 897   34 A2   863  
12 A2 746 736   -15 A2   751  
13 A2 345 340   -81 A2   421  
14 B1 940 927    B1     760 reassinged to mode 15
15 B1 732 722   -38 B1   760 696 questionable
16 B1 340 335   -35 B1   370  
17 B2 3131 3088   13 B2   3075  
18 B2 3111 3068   25 B2   3043  
19 B2 1565 1543   -22 B2   1565  
20 B2 1392 1373   -71 B2   1444  
21 B2 1271 1254   15 B2   1239  
22 B2 1057 1043   -9 B2   1052  
23 B2 1020 1006   -3 B2   1009  
24 B2 609 601   -63 B2   664  
The calculated vibrational frequencies were scaled by 0.9863

See section Calculated; Vibrations; Scale Factors; Set scaling factors to change the scale factors used here.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to determine the least squares best scaling factor.
See section Calculated; Vibrations; Scale Factors; Scale factor uncertainty for information on where the above scaling factor is from.