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Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

PBEPBE/3-21G

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 3158 3129   66 A1   3063  
2 A1 3121 3093   50 A1   3043  
3 A1 1548 1534   -38 A1   1572  
4 A1 1400 1387   -27 A1   1414  
5 A1 1187 1177   -106 A1   1283  
6 A1 1111 1100   -60 A1   1160  
7 A1 1023 1014   -49 A1   1063  
8 A1 834 826   -138 A1   964  
9 A1 668 662   43 A1   619  
10 A2 1018 1009   73 A2   936  
11 A2 933 925   62 A2   863  
12 A2 758 751   0 A2   751  
13 A2 341 338   -83 A2   421  
14 B1 977 968    B1     760 reassinged to mode 15
15 B1 749 742   -18 B1   760 696 questionable
16 B1 346 343   -27 B1   370  
17 B2 3141 3112   37 B2   3075  
18 B2 3118 3089   46 B2   3043  
19 B2 1510 1496   -69 B2   1565  
20 B2 1400 1387   -57 B2   1444  
21 B2 1266 1255   16 B2   1239  
22 B2 1054 1045   -7 B2   1052  
23 B2 1005 996   -13 B2   1009  
24 B2 617 612   -52 B2   664  
The calculated vibrational frequencies were scaled by 0.9909

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.