return to home page

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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

LSDA/6-311G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3073 10 A1 3063  
2 A1 3043 0 A1 3043  
3 A1 1576 4 A1 1572  
4 A1 1426 12 A1 1414  
5 A1 1225 -58 A1 1283  
6 A1 1118 -42 A1 1160  
7 A1 1066 3 A1 1063  
8 A1 1007 43 A1 964  
9 A1 655 36 A1 619  
10 A2 959 23 A2 936  
11 A2 891 28 A2 863  
12 A2 750 -1 A2 751  
13 A2 337 -84 A2 421  
14 B1 927   B1   760 reassinged to mode 15
15 B1 714 -46 B1 760 696 questionable
16 B1 334 -36 B1 370  
17 B2 3059 -16 B2 3075  
18 B2 3040 -3 B2 3043  
19 B2 1566 1 B2 1565  
20 B2 1379 -65 B2 1444  
21 B2 1256 17 B2 1239  
22 B2 1046 -6 B2 1052  
23 B2 1013 4 B2 1009  
24 B2 606 -58 B2 664  
The calculated vibrational frequencies were scaled by 0.9837

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.