National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
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IXFeedback
XOlder CCCBDB versions
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XIII Vibrations
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XVEntropy data
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XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

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

Compare vibrational frequencies for two calculations for HNO2 (Nitrous acid)

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 A' A'   3667 3488 178.9 1.051   1.067 1.066 0.001 1.001   124.75 78.90 45.85 1.581
2 A' A'   1837 1567 269.8 1.172   10.382 8.395 1.986 1.237   152.17 63.91 88.27 2.381
3 A' A'   1361 1244 116.5 1.094   1.286 1.307 -0.020 0.984   262.73 198.60 64.13 1.323
4 A' A'   986 816 170.1 1.208   7.404 6.597 0.807 1.122   226.31 184.91 41.40 1.224
5 A' A'   710 593 116.5 1.196   7.797 9.702 -1.905 0.804   19.60 99.63 -80.03 0.197
6 A" A"   539 571 -32.0 0.944   1.159 1.159 -0.000 1.000   137.23 120.06 17.17 1.143
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.