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

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

HF/CEP-121G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 2996 -22 Ag 3018  
2 Ag 2901 -29 Ag 2930  
3 Ag 1800 81 Ag 1719  
4 Ag 1441 17 Ag 1424  
5 Ag 1397 31 Ag 1366  
6 Ag 1276 2 Ag 1274  
7 Ag 1001 -3 Ag 1004  
8 Ag 669 -16 Ag 685  
9 Ag 512 -102 Ag 614  
10 Ag 343 -26 Ag 369  
11 Au 2965 -25 Au 2990  
12 Au 1441 20 Au 1421  
13 Au 961 -150 Au 1111  
14 Au 348 9 Au 339  
15 Au 115        
16 Au 41 -7 Au 48  
17 Bg 2965 -13 Bg 2978  
18 Bg 1444 20 Bg 1424  
19 Bg 1062 -47 Bg 1109  
20 Bg 605 67 Bg 538  
21 Bg 115 -125 Bg 240  
22 Bu 2997 -14 Bu 3011  
23 Bu 2900 -26 Bu 2926  
24 Bu 1771 53 Bu 1718  
25 Bu 1441 20 Bu 1421  
26 Bu 1385 32 Bu 1353  
27 Bu 1106 -5 Bu 1111  
28 Bu 888 -39 Bu 927  
29 Bu 523 -11 Bu 534  
30 Bu 225 -25 Bu 250  
The calculated vibrational frequencies were scaled by 0.9034

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.