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

Compare vibrational frequencies in CCCBDB for CH3COOH (Acetic acid)

QCISD/3-21G

Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 A' 3385 -198 A' 3583  
2 A' 3059 8 A' 3051  
3 A' 2964 20 A' 2944  
4 A' 1719 -69 A' 1788  
5 A' 1504 74 A' 1430  
6 A' 1417 35 A' 1382  
7 A' 1350 86 A' 1264  
8 A' 1150 -32 A' 1182  
9 A' 974 -15 A' 989  
10 A' 797 -50 A' 847  
11 A' 547 -110 A' 657  
12 A' 390   A'   questionable (581 listed)
13 A" 3024 28 A" 2996  
14 A" 1509 79 A" 1430  
15 A" 1084 36 A" 1048  
16 A" 630 -12 A" 642  
17 A" 526 -8 A" 534  
18 A" 106 13 A" 93  
The calculated vibrational frequencies were scaled by 0.9692

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.