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Compare vibrational frequencies in CCCBDB for CH3COOH (Acetic acid)

MP2/CEP-121G*

18 11 26 13 55
Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency Scaled
Frequency
Harm.
diff
Fund.
diff
Symmetry Harmonic
Frequency
Fundamental
Frequency
Comment
1 A' 3712 3537   -46 A'   3583  
2 A' 3231 3078   27 A'   3051  
3 A' 3096 2950   6 A'   2944  
4 A' 1797 1712   -76 A'   1788  
5 A' 1515 1443   13 A'   1430  
6 A' 1448 1379   -3 A'   1382  
7 A' 1355 1291   27 A'   1264  
8 A' 1229 1171   -11 A'   1182  
9 A' 1020 972   -17 A'   989  
10 A' 863 823   -24 A'   847  
11 A' 574 547   -110 A'   657  
12 A' 418 398    A'     questionable (581 listed)
13 A" 3191 3040   44 A"   2996  
14 A" 1512 1441   11 A"   1430  
15 A" 1082 1031   -17 A"   1048  
16 A" 664 633   -9 A"   642  
17 A" 540 515   -19 A"   534  
18 A" 55 52   -41 A"   93  
The calculated vibrational frequencies were scaled by 0.9528

See section Calculated; Vibrations; Scale Factors; Set scaling factors to change the scale factors used here.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to determine the least squares best scaling factor.
See section Calculated; Vibrations; Scale Factors; Scale factor uncertainty for information on where the above scaling factor is from.