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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

MP2/6-31G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3098 35 A1 3063  
2 A1 3078 35 A1 3043  
3 A1 1512 -60 A1 1572  
4 A1 1389 -25 A1 1414  
5 A1 1169 -114 A1 1283  
6 A1 1114 -46 A1 1160  
7 A1 1004 -59 A1 1063  
8 A1 825 -139 A1 964  
9 A1 648 29 A1 619  
10 A2 882 -54 A2 936  
11 A2 860 -3 A2 863  
12 A2 644 -107 A2 751  
13 A2 344 -77 A2 421  
14 B1 886   B1   760 reassinged to mode 15
15 B1 712 -48 B1 760 696 questionable
16 B1 350 -20 B1 370  
17 B2 3092 17 B2 3075  
18 B2 3064 21 B2 3043  
19 B2 1498 -67 B2 1565  
20 B2 1378 -66 B2 1444  
21 B2 1241 2 B2 1239  
22 B2 1045 -7 B2 1052  
23 B2 997 -12 B2 1009  
24 B2 607 -57 B2 664  
The calculated vibrational frequencies were scaled by 0.9568

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.