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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

B3PW91/STO-3G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3096 33 A1 3063  
2 A1 3060 17 A1 3043  
3 A1 1488 -84 A1 1572  
4 A1 1338 -76 A1 1414  
5 A1 1085 -198 A1 1283  
6 A1 1025 -135 A1 1160  
7 A1 961 -102 A1 1063  
8 A1 872 -92 A1 964  
9 A1 595 -24 A1 619  
10 A2 935 -1 A2 936  
11 A2 850 -13 A2 863  
12 A2 678 -73 A2 751  
13 A2 318 -103 A2 421  
14 B1 888   B1   760 reassinged to mode 15
15 B1 685 -75 B1 760 696 questionable
16 B1 316 -54 B1 370  
17 B2 3082 7 B2 3075  
18 B2 3056 13 B2 3043  
19 B2 1482 -83 B2 1565  
20 B2 1313 -131 B2 1444  
21 B2 1160 -79 B2 1239  
22 B2 993 -59 B2 1052  
23 B2 940 -69 B2 1009  
24 B2 563 -101 B2 664  
The calculated vibrational frequencies were scaled by 0.885

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.