National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
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 C2H3 (vinyl)

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'   3081 3147 -65.8 0.979   1.095 1.111 -0.017 0.985   3.81 1.96 1.85 1.947
2 A' A'   3030 3086 -56.0 0.982   1.109 1.108 0.001 1.001   12.07 3.95 8.12 3.059
3 A' A'   2946 2993 -46.8 0.984   1.057 1.063 -0.006 0.995   9.60 2.15 7.45 4.461
4 A' A'   1469 1753 -283.7 0.838   1.504 5.758 -4.254 0.261   1.49 2.31 -0.82 0.645
5 A' A'   1265 1382 -117.2 0.915   2.441 1.083 1.357 2.253   3.39 7.83 -4.44 0.433
6 A' A'   1075 1057 17.8 1.017   1.471 1.507 -0.036 0.976   8.34 11.40 -3.05 0.732
7 A' A'   745 726 18.4 1.025   1.053 1.054 -0.001 0.999   12.52 21.12 -8.60 0.593
8 A" A"   861 1004 -142.2 0.858   1.194 1.212 -0.018 0.985   69.97 87.56 -17.59 0.799
9 A" A"   795 936 -141.1 0.849   1.270 1.272 -0.002 0.999   2.47 10.54 -8.07 0.234
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.