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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

MP3/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3074 11 A1 3063  
2 A1 3055 12 A1 3043  
3 A1 1574 2 A1 1572  
4 A1 1432 18 A1 1414  
5 A1 1137 -146 A1 1283  
6 A1 1119 -41 A1 1160  
7 A1 1053 -10 A1 1063  
8 A1 951 -13 A1 964  
9 A1 649 30 A1 619  
10 A2 895 -41 A2 936  
11 A2 888 25 A2 863  
12 A2 666 -85 A2 751  
13 A2 346 -75 A2 421  
14 B1 899   B1   760 reassinged to mode 15
15 B1 723 -37 B1 760 696 questionable
16 B1 365 -5 B1 370  
17 B2 3064 -11 B2 3075  
18 B2 3049 6 B2 3043  
19 B2 1573 8 B2 1565  
20 B2 1393 -51 B2 1444  
21 B2 1271 32 B2 1239  
22 B2 1048 -4 B2 1052  
23 B2 1011 2 B2 1009  
24 B2 600 -64 B2 664  
The calculated vibrational frequencies were scaled by 0.9386

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.