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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

MP2/6-311G**

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3083 20 A1 3063  
2 A1 3060 17 A1 3043  
3 A1 1525 -47 A1 1572  
4 A1 1403 -11 A1 1414  
5 A1 1232 -51 A1 1283  
6 A1 1110 -50 A1 1160  
7 A1 1039 -24 A1 1063  
8 A1 947 -17 A1 964  
9 A1 637 18 A1 619  
10 A2 902 -34 A2 936  
11 A2 879 16 A2 863  
12 A2 643 -108 A2 751  
13 A2 332 -89 A2 421  
14 B1 903   B1   760 reassinged to mode 15
15 B1 719 -41 B1 760 696 questionable
16 B1 348 -22 B1 370  
17 B2 3071 -4 B2 3075  
18 B2 3055 12 B2 3043  
19 B2 1524 -41 B2 1565  
20 B2 1354 -90 B2 1444  
21 B2 1238 -1 B2 1239  
22 B2 1028 -24 B2 1052  
23 B2 1004 -5 B2 1009  
24 B2 589 -75 B2 664  
The calculated vibrational frequencies were scaled by 0.9502

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.