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 C2F4 (Tetrafluoroethylene)


Frequency in cm-1
  Calculated   Experimental
Mode Number Symmetry Frequency diff Symmetry Frequency Comment
1 Ag 1749 -123 Ag 1872  
2 Ag 668 -110 Ag 778  
3 Ag 336 -58 Ag 394  
4 Au 175 -15 Au 190  
5 B1u 1025 -161 B1u 1186  
6 B1u 464 -94 B1u 558  
7 B2g 375 -133 B2g 508  
8 B2u 1162 -175 B2u 1337  
9 B2u 186 -32 B2u 218  
10 B3g 1167 -173 B3g 1340  
11 B3g 483 -68 B3g 551  
12 B3u 341 -65 B3u 406  
The calculated vibrational frequencies were scaled by 0.9663

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.