National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
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

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to

return to home page

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 2921 78 Ag 2843  
2 Ag 1750 5 Ag 1745  
3 Ag 1349 11 Ag 1338  
4 Ag 1001 -64 Ag 1065  
5 Ag 542 -9 Ag 551  
6 Au 855 54 Au 801  
7 Au 189 62 Au 127  
8 Bg 1099 51 Bg 1048  
9 Bu 2923 88 Bu 2835  
10 Bu 1721 -11 Bu 1732  
11 Bu 1323 11 Bu 1312  
12 Bu 320 -19 Bu 339  
The calculated vibrational frequencies were scaled by 0.9026

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.