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

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

mPW1PW91/6-311G**

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 3050 32 Ag 3018  
2 Ag 2938 8 Ag 2930  
3 Ag 1754 35 Ag 1719  
4 Ag 1393 -31 Ag 1424  
5 Ag 1339 -27 Ag 1366  
6 Ag 1241 -33 Ag 1274  
7 Ag 971 -33 Ag 1004  
8 Ag 669 -16 Ag 685  
9 Ag 508 -106 Ag 614  
10 Ag 347 -22 Ag 369  
11 Au 3002 12 Au 2990  
12 Au 1393 -28 Au 1421  
13 Au 913 -198 Au 1111  
14 Au 338 -1 Au 339  
15 Au 101        
16 Au 45 -3 Au 48  
17 Bg 3002 24 Bg 2978  
18 Bg 1399 -25 Bg 1424  
19 Bg 1026 -83 Bg 1109  
20 Bg 601 63 Bg 538  
21 Bg 91 -149 Bg 240  
22 Bu 3050 39 Bu 3011  
23 Bu 2938 12 Bu 2926  
24 Bu 1753 35 Bu 1718  
25 Bu 1394 -27 Bu 1421  
26 Bu 1326 -27 Bu 1353  
27 Bu 1093 -18 Bu 1111  
28 Bu 882 -45 Bu 927  
29 Bu 523 -11 Bu 534  
30 Bu 228 -22 Bu 250  
The calculated vibrational frequencies were scaled by 0.9567

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.