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 C2F4 (Tetrafluoroethylene)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 1632 -240 Ag 1872  
2 Ag 705 -73 Ag 778  
3 Ag 316 -78 Ag 394  
4 Au 156 -34 Au 190  
5 B1u 1090 -96 B1u 1186  
6 B1u 445 -113 B1u 558  
7 B2g 366 -142 B2g 508  
8 B2u 1258 -79 B2u 1337  
9 B2u 154 -64 B2u 218  
10 B3g 1311 -29 B3g 1340  
11 B3g 466 -85 B3g 551  
12 B3u 354 -52 B3u 406  
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.