National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 19April 2018
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 C2H4 (Ethylene)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1   -3026 Ag 3026  
2   -1623 Ag 1623  
3   -1342 Ag 1342  
4   -1023 Au 1023  
5   -2989 B1u 2989 sym was B3U
6   -1444 B1u 1444 sym was B3U
7   -940 B2g 940  
8   -3105 B2u 3105  
9   -826 B2u 826  
10   -3086 B3g 3086 sym was B1G
11   -1217 B3g 1217 sym was B1G
12   -949 B3u 949 sym was B1U
The calculated vibrational frequencies were scaled by 0.936

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.