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
XIIGeometries
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 C6H5CHCH2 (Styrene)

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'   3072 3120 -48.5 0.984   1.116 1.117 -0.000 1.000   22.25 11.13 11.12 1.999
2 A A'   3046 3061 -15.3 0.995   1.098 1.099 -0.001 0.999   11.80 12.21 -0.40 0.967
3 A A'   3038 3053 -14.6 0.995   1.095 1.094 0.001 1.001   46.78 27.22 19.56 1.718
4 A A'   3028 3046 -17.2 0.994   1.093 1.090 0.003 1.003   34.54 9.40 25.14 3.675
5 A A'   3018 3038 -20.3 0.993   1.089 1.075 0.014 1.013   0.79 1.33 -0.53 0.598
6 A A'   3012 3035 -23.2 0.992   1.087 1.078 0.009 1.008   10.87 0.07 10.80 163.417
7 A A'   3006 3027 -21.2 0.993   1.077 1.088 -0.011 0.990   4.77 9.07 -4.31 0.525
8 A A'   2992 3011 -19.0 0.994   1.076 1.086 -0.010 0.991   13.52 12.74 0.78 1.061
9 A A'   1678 1619 58.7 1.036   4.231 4.152 0.079 1.019   7.06 3.95 3.10 1.785
10 A A'   1626 1582 43.4 1.027   5.152 5.618 -0.466 0.917   4.36 1.44 2.92 3.020
11 A A'   1598 1558 39.4 1.025   4.883 5.166 -0.283 0.945   4.01 2.34 1.67 1.714
12 A A'   1502 1469 33.7 1.023   2.164 2.234 -0.070 0.968   15.80 11.85 3.95 1.333
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.