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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 3086 23 A1 3063  
2 A1 3056 13 A1 3043  
3 A1 1580 8 A1 1572  
4 A1 1427 13 A1 1414  
5 A1 1242 -41 A1 1283  
6 A1 1115 -45 A1 1160  
7 A1 1068 5 A1 1063  
8 A1 1008 44 A1 964  
9 A1 650 31 A1 619  
10 A2 964 28 A2 936  
11 A2 893 30 A2 863  
12 A2 747 -4 A2 751  
13 A2 336 -85 A2 421  
14 B1 928   B1   760 reassinged to mode 15
15 B1 716 -44 B1 760 696 questionable
16 B1 332 -38 B1 370  
17 B2 3073 -2 B2 3075  
18 B2 3052 9 B2 3043  
19 B2 1571 6 B2 1565  
20 B2 1375 -69 B2 1444  
21 B2 1251 12 B2 1239  
22 B2 1046 -6 B2 1052  
23 B2 1004 -5 B2 1009  
24 B2 600 -64 B2 664  
The calculated vibrational frequencies were scaled by 0.9813

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.