National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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

Compare vibrational frequencies in CCCBDB for C2H2O2 (Ethanedial)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 2931 88 Ag 2843  
2 Ag 1756 11 Ag 1745  
3 Ag 1353 15 Ag 1338  
4 Ag 1004 -61 Ag 1065  
5 Ag 544 -7 Ag 551  
6 Au 858 57 Au 801  
7 Au 190 63 Au 127  
8 Bg 1103 55 Bg 1048  
9 Bu 2933 98 Bu 2835  
10 Bu 1727 -5 Bu 1732  
11 Bu 1327 15 Bu 1312  
12 Bu 321 -18 Bu 339  
The calculated vibrational frequencies were scaled by 0.9056

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.