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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

LSDA/6-31G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3107 44 A1 3063  
2 A1 3088 45 A1 3043  
3 A1 1563 -9 A1 1572  
4 A1 1414 -0 A1 1414  
5 A1 1204 -79 A1 1283  
6 A1 1131 -29 A1 1160  
7 A1 1054 -9 A1 1063  
8 A1 960 -4 A1 964  
9 A1 660 41 A1 619  
10 A2 991 55 A2 936  
11 A2 912 49 A2 863  
12 A2 749 -2 A2 751  
13 A2 345 -76 A2 421  
14 B1 956   B1   760 reassinged to mode 15
15 B1 733 -27 B1 760 696 questionable
16 B1 337 -33 B1 370  
17 B2 3097 22 B2 3075  
18 B2 3078 35 B2 3043  
19 B2 1546 -19 B2 1565  
20 B2 1379 -65 B2 1444  
21 B2 1262 23 B2 1239  
22 B2 1058 6 B2 1052  
23 B2 998 -11 B2 1009  
24 B2 613 -51 B2 664  
The calculated vibrational frequencies were scaled by 0.9797

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.