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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

mPW1PW91/STO-3G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3098 35 A1 3063  
2 A1 3064 21 A1 3043  
3 A1 1493 -79 A1 1572  
4 A1 1342 -72 A1 1414  
5 A1 1084 -199 A1 1283  
6 A1 1027 -133 A1 1160  
7 A1 967 -96 A1 1063  
8 A1 883 -81 A1 964  
9 A1 596 -23 A1 619  
10 A2 939 3 A2 936  
11 A2 853 -10 A2 863  
12 A2 681 -70 A2 751  
13 A2 321 -100 A2 421  
14 B1 892   B1   760 reassinged to mode 15
15 B1 688 -72 B1 760 696 questionable
16 B1 321 -49 B1 370  
17 B2 3084 9 B2 3075  
18 B2 3059 16 B2 3043  
19 B2 1489 -76 B2 1565  
20 B2 1316 -128 B2 1444  
21 B2 1164 -75 B2 1239  
22 B2 996 -56 B2 1052  
23 B2 941 -68 B2 1009  
24 B2 564 -100 B2 664  
The calculated vibrational frequencies were scaled by 0.8789

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.