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

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 C2Cl4 (Tetrachloroethylene)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 1533 -38 Ag 1571  
2 Ag 421 -26 Ag 447  
3 Ag 231 -6 Ag 237  
4 Au 89 -21 Au 110  
5 B1u 723 -54 B1u 777  
6 B1u 303 -7 B1u 310  
7 B2g 488 -24 B2g 512  
8 B2u 817 -91 B2u 908  
9 B2u 172 -4 B2u 176  
10 B3g 898 -102 B3g 1000  
11 B3g 326 -21 B3g 347  
12 B3u 277 -11 B3u 288  
The calculated vibrational frequencies were scaled by 0.9947

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.