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

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

B3LYP/6-31G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3060 42 Ag 3018  
2 Ag 2945 15 Ag 2930  
3 Ag 1653 -66 Ag 1719  
4 Ag 1442 18 Ag 1424  
5 Ag 1390 24 Ag 1366  
6 Ag 1257 -17 Ag 1274  
7 Ag 1004 -0 Ag 1004  
8 Ag 670 -15 Ag 685  
9 Ag 517 -97 Ag 614  
10 Ag 358 -11 Ag 369  
11 Au 3005 15 Au 2990  
12 Au 1447 26 Au 1421  
13 Au 968 -143 Au 1111  
14 Au 350 11 Au 339  
15 Au 107        
16 Au 56 8 Au 48  
17 Bg 3006 28 Bg 2978  
18 Bg 1451 27 Bg 1424  
19 Bg 1056 -53 Bg 1109  
20 Bg 617 79 Bg 538  
21 Bg 97 -143 Bg 240  
22 Bu 3060 49 Bu 3011  
23 Bu 2945 19 Bu 2926  
24 Bu 1649 -69 Bu 1718  
25 Bu 1445 24 Bu 1421  
26 Bu 1388 35 Bu 1353  
27 Bu 1126 15 Bu 1111  
28 Bu 912 -15 Bu 927  
29 Bu 529 -5 Bu 534  
30 Bu 237 -13 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.