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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

PBEPBE/STO-3G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3112 49 A1 3063  
2 A1 3073 30 A1 3043  
3 A1 1481 -91 A1 1572  
4 A1 1332 -82 A1 1414  
5 A1 1091 -192 A1 1283  
6 A1 1030 -130 A1 1160  
7 A1 951 -112 A1 1063  
8 A1 839 -125 A1 964  
9 A1 592 -27 A1 619  
10 A2 923 -13 A2 936  
11 A2 840 -23 A2 863  
12 A2 672 -79 A2 751  
13 A2 302 -119 A2 421  
14 B1 876   B1   760 reassinged to mode 15
15 B1 675 -85 B1 760 696 questionable
16 B1 292 -78 B1 370  
17 B2 3098 23 B2 3075  
18 B2 3069 26 B2 3043  
19 B2 1471 -94 B2 1565  
20 B2 1308 -136 B2 1444  
21 B2 1150 -89 B2 1239  
22 B2 984 -68 B2 1052  
23 B2 944 -65 B2 1009  
24 B2 562 -102 B2 664  
The calculated vibrational frequencies were scaled by 0.9136

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.