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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

LSDA/3-21G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3102 39 A1 3063  
2 A1 3067 24 A1 3043  
3 A1 1548 -24 A1 1572  
4 A1 1390 -24 A1 1414  
5 A1 1180 -103 A1 1283  
6 A1 1126 -34 A1 1160  
7 A1 1039 -24 A1 1063  
8 A1 887 -77 A1 964  
9 A1 668 49 A1 619  
10 A2 1008 72 A2 936  
11 A2 918 55 A2 863  
12 A2 765 14 A2 751  
13 A2 335 -86 A2 421  
14 B1 969   B1   760 reassinged to mode 15
15 B1 734 -26 B1 760 696 questionable
16 B1 341 -29 B1 370  
17 B2 3086 11 B2 3075  
18 B2 3064 21 B2 3043  
19 B2 1514 -51 B2 1565  
20 B2 1379 -65 B2 1444  
21 B2 1263 24 B2 1239  
22 B2 1053 1 B2 1052  
23 B2 1002 -7 B2 1009  
24 B2 616 -48 B2 664  
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.