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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

LSDA/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3107 44 A1 3063  
2 A1 3072 29 A1 3043  
3 A1 1550 -22 A1 1572  
4 A1 1392 -22 A1 1414  
5 A1 1182 -101 A1 1283  
6 A1 1127 -33 A1 1160  
7 A1 1041 -22 A1 1063  
8 A1 888 -76 A1 964  
9 A1 669 50 A1 619  
10 A2 1009 73 A2 936  
11 A2 920 57 A2 863  
12 A2 767 16 A2 751  
13 A2 336 -85 A2 421  
14 B1 971   B1   760 reassinged to mode 15
15 B1 736 -24 B1 760 696 questionable
16 B1 342 -28 B1 370  
17 B2 3091 16 B2 3075  
18 B2 3069 26 B2 3043  
19 B2 1517 -48 B2 1565  
20 B2 1381 -63 B2 1444  
21 B2 1265 26 B2 1239  
22 B2 1055 3 B2 1052  
23 B2 1003 -6 B2 1009  
24 B2 617 -47 B2 664  
The calculated vibrational frequencies were scaled by 0.9836

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.