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

Compare vibrational frequencies in CCCBDB for C4H4N2 (Pyridazine)

PBEPBE/cc-pVTZ

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A1 3102 39 A1 3063  
2 A1 3071 28 A1 3043  
3 A1 1551 -21 A1 1572  
4 A1 1421 7 A1 1414  
5 A1 1165 -118 A1 1283  
6 A1 1124 -36 A1 1160  
7 A1 1055 -8 A1 1063  
8 A1 976 12 A1 964  
9 A1 652 33 A1 619  
10 A2 980 44 A2 936  
11 A2 907 44 A2 863  
12 A2 755 4 A2 751  
13 A2 345 -76 A2 421  
14 B1 943   B1   760 reassinged to mode 15
15 B1 727 -33 B1 760 696 questionable
16 B1 337 -33 B1 370  
17 B2 3088 13 B2 3075  
18 B2 3067 24 B2 3043  
19 B2 1544 -21 B2 1565  
20 B2 1381 -63 B2 1444  
21 B2 1259 20 B2 1239  
22 B2 1048 -4 B2 1052  
23 B2 1019 10 B2 1009  
24 B2 607 -57 B2 664  
The calculated vibrational frequencies were scaled by 0.9931

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.