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

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III.G.7. (XIII.B.3.) (XIII.D.5.)

Compare vibrational frequencies for two calculations for AsO2 (Aresenic dioxide)

A = HF/6-31G*

B = MP2/6-31G*

scale factors=0.8985, 0.943
  symmetry   frequency (cm-1)   reduced mass (amu)   IR Intensity (km mol-1)
mode number A B   A B diff. ratio   A B diff. ratio   A B diff. ratio
1 A1 A1   869 937 -67.6 0.928   16.878 16.931 -0.054 0.997   0.45 10.51 -10.06 0.043
2 A1 A1   260 284 -24.4 0.914   19.579 19.507 0.072 1.004   17.05 34.26 -17.21 0.498
3 B2 B2   1179 6176 -4996.7 0.191   19.901 20.218 -0.317 0.984   1064.19 1454910.00 -1453846.00 0.001
scaled by     0.8985 0.943

See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.