return to home page

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

Compare vibrational frequencies in CCCBDB for C4H6O2 (2,3-Butanedione)

BLYP/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3067 49 Ag 3018  
2 Ag 2960 30 Ag 2930  
3 Ag 1698 -21 Ag 1719  
4 Ag 1436 12 Ag 1424  
5 Ag 1361 -5 Ag 1366  
6 Ag 1222 -52 Ag 1274  
7 Ag 980 -24 Ag 1004  
8 Ag 648 -37 Ag 685  
9 Ag 494 -120 Ag 614  
10 Ag 349 -20 Ag 369  
11 Au 3011 21 Au 2990  
12 Au 1439 18 Au 1421  
13 Au 932 -179 Au 1111  
14 Au 328 -11 Au 339  
15 Au 110        
16 Au 54 6 Au 48  
17 Bg 3011 33 Bg 2978  
18 Bg 1444 20 Bg 1424  
19 Bg 1033 -76 Bg 1109  
20 Bg 599 61 Bg 538  
21 Bg 106 -134 Bg 240  
22 Bu 3067 56 Bu 3011  
23 Bu 2960 34 Bu 2926  
24 Bu 1704 -14 Bu 1718  
25 Bu 1438 17 Bu 1421  
26 Bu 1358 5 Bu 1353  
27 Bu 1098 -13 Bu 1111  
28 Bu 872 -55 Bu 927  
29 Bu 520 -14 Bu 534  
30 Bu 231 -19 Bu 250  
The calculated vibrational frequencies were scaled by 0.9919

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.