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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

LSDA/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3088 25 A1 3063  
2 A1 3061 18 A1 3043  
3 A1 1583 11 A1 1572  
4 A1 1434 20 A1 1414  
5 A1 1245 -38 A1 1283  
6 A1 1120 -40 A1 1160  
7 A1 1071 8 A1 1063  
8 A1 1009 45 A1 964  
9 A1 651 32 A1 619  
10 A2 962 26 A2 936  
11 A2 894 31 A2 863  
12 A2 747 -4 A2 751  
13 A2 337 -84 A2 421  
14 B1 926   B1   760 reassinged to mode 15
15 B1 717 -43 B1 760 696 questionable
16 B1 333 -37 B1 370  
17 B2 3075 0 B2 3075  
18 B2 3057 14 B2 3043  
19 B2 1574 9 B2 1565  
20 B2 1381 -63 B2 1444  
21 B2 1259 20 B2 1239  
22 B2 1050 -2 B2 1052  
23 B2 1005 -4 B2 1009  
24 B2 600 -64 B2 664  
The calculated vibrational frequencies were scaled by 0.9813

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.