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

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

B3LYP/3-21G*

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3052 34 Ag 3018  
2 Ag 2952 22 Ag 2930  
3 Ag 1681 -38 Ag 1719  
4 Ag 1454 30 Ag 1424  
5 Ag 1388 22 Ag 1366  
6 Ag 1203 -71 Ag 1274  
7 Ag 986 -18 Ag 1004  
8 Ag 640 -45 Ag 685  
9 Ag 522 -92 Ag 614  
10 Ag 361 -8 Ag 369  
11 Au 3000 10 Au 2990  
12 Au 1471 50 Au 1421  
13 Au 973 -138 Au 1111  
14 Au 374 35 Au 339  
15 Au 115        
16 Au 17 -31 Au 48  
17 Bg 3001 23 Bg 2978  
18 Bg 1476 52 Bg 1424  
19 Bg 1072 -37 Bg 1109  
20 Bg 654 116 Bg 538  
21 Bg 48 -192 Bg 240  
22 Bu 3053 42 Bu 3011  
23 Bu 2952 26 Bu 2926  
24 Bu 1677 -41 Bu 1718  
25 Bu 1457 36 Bu 1421  
26 Bu 1387 34 Bu 1353  
27 Bu 1109 -2 Bu 1111  
28 Bu 876 -51 Bu 927  
29 Bu 514 -20 Bu 534  
30 Bu 242 -8 Bu 250  
The calculated vibrational frequencies were scaled by 0.962

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.