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 CH3OHH2O (methanol water dimer)

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'   3657 3548 109.4 1.031   1.051 1.046 0.005 1.005   36.39 10.91 25.47 3.334
2 A' A'   3642 3486 155.7 1.045   1.062 1.066 -0.004 0.996   311.63 372.68 -61.05 0.836
3 A' A'   2952 3020 -67.9 0.978   1.098 1.100 -0.002 0.998   69.81 44.19 25.62 1.580
4 A' A'   2852 2888 -35.9 0.988   1.037 1.035 0.002 1.002   72.22 62.11 10.11 1.163
5 A' A'   1638 1631 6.7 1.004   1.082 1.082 -0.000 1.000   109.47 92.70 16.77 1.181
6 A' A'   1497 1491 5.9 1.004   1.051 1.048 0.003 1.003   2.06 1.95 0.11 1.058
7 A' A'   1473 1453 20.1 1.014   1.162 1.161 0.001 1.001   14.16 8.53 5.63 1.661
8 A' A'   1400 1403 -3.3 0.998   1.238 1.195 0.043 1.036   64.22 50.96 13.26 1.260
9 A' A'   1086 1084 1.9 1.002   1.175 1.174 0.001 1.000   10.87 12.81 -1.94 0.849
10 A' A'   1078 1047 31.5 1.030   4.900 5.683 -0.782 0.862   126.48 96.10 30.38 1.316
11 A' A'   240 293 -52.5 0.821   1.414 1.350 0.064 1.047   282.69 281.77 0.92 1.003
12 A' A'   146 176 -30.3 0.828   3.634 3.885 -0.251 0.935   13.96 6.65 7.31 2.100
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.