return to home page

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

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

CCD/6-31G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3035 17 Ag 3018  
2 Ag 2930 -0 Ag 2930  
3 Ag 1764 45 Ag 1719  
4 Ag 1437 13 Ag 1424  
5 Ag 1382 16 Ag 1366  
6 Ag 1284 10 Ag 1274  
7 Ag 994 -10 Ag 1004  
8 Ag 682 -3 Ag 685  
9 Ag 518 -96 Ag 614  
10 Ag 353 -16 Ag 369  
11 Au 3000 10 Au 2990  
12 Au 1435 14 Au 1421  
13 Au 951 -160 Au 1111  
14 Au 339 0 Au 339  
15 Au 123        
16 Au 58 10 Au 48  
17 Bg 3000 22 Bg 2978  
18 Bg 1437 13 Bg 1424  
19 Bg 1041 -68 Bg 1109  
20 Bg 597 59 Bg 538  
21 Bg 124 -116 Bg 240  
22 Bu 3036 25 Bu 3011  
23 Bu 2930 4 Bu 2926  
24 Bu 1753 35 Bu 1718  
25 Bu 1437 16 Bu 1421  
26 Bu 1370 17 Bu 1353  
27 Bu 1113 2 Bu 1111  
28 Bu 905 -22 Bu 927  
29 Bu 525 -9 Bu 534  
30 Bu 233 -17 Bu 250  
The calculated vibrational frequencies were scaled by 0.9465

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.