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 Ag 3051 25 Ag 3026  
2 Ag 1586 -37 Ag 1623  
3 Ag 1330 -12 Ag 1342  
4 Au 1007 -16 Au 1023  
5 B1u 3024 36 B1u 2989 sym was B3U
6 B1u 1458 15 B1u 1444 sym was B3U
7 B2g 782 -157 B2g 940  
8 B2u 3160 55 B2u 3105  
9 B2u 798 -28 B2u 826  
10 B3g 3125 39 B3g 3086 sym was B1G
11 B3g 1220 3 B3g 1217 sym was B1G
12 B3u 928 -21 B3u 949 sym was B1U
The calculated vibrational frequencies were scaled by 0.9653

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.