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 C2Cl4 (Tetrachloroethylene)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 1556 -15 Ag 1571  
2 Ag 410 -37 Ag 447  
3 Ag 203 -34 Ag 237  
4 Au 89 -21 Au 110  
5 B1u 728 -49 B1u 777  
6 B1u 263 -47 B1u 310  
7 B2g 442 -70 B2g 512  
8 B2u 902 -6 B2u 908  
9 B2u 158 -18 B2u 176  
10 B3g 977 -23 B3g 1000  
11 B3g 306 -41 B3g 347  
12 B3u 255 -33 B3u 288  
The calculated vibrational frequencies were scaled by 0.883

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.