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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

MP2/STO-3G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3081 18 A1 3063  
2 A1 3050 7 A1 3043  
3 A1 1451 -121 A1 1572  
4 A1 1295 -119 A1 1414  
5 A1 1071 -212 A1 1283  
6 A1 985 -175 A1 1160  
7 A1 893 -170 A1 1063  
8 A1 785 -179 A1 964  
9 A1 584 -35 A1 619  
10 A2 931 -5 A2 936  
11 A2 851 -12 A2 863  
12 A2 677 -74 A2 751  
13 A2 326 -95 A2 421  
14 B1 883   B1   760 reassinged to mode 15
15 B1 684 -76 B1 760 696 questionable
16 B1 332 -38 B1 370  
17 B2 3069 -6 B2 3075  
18 B2 3049 6 B2 3043  
19 B2 1440 -125 B2 1565  
20 B2 1304 -140 B2 1444  
21 B2 1144 -95 B2 1239  
22 B2 977 -75 B2 1052  
23 B2 949 -60 B2 1009  
24 B2 556 -108 B2 664  
The calculated vibrational frequencies were scaled by 0.8719

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.