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
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
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 C5H8 (Cyclopentene)

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'   3045 3076 -30.6 0.990   1.105 1.104 0.001 1.001   31.84 20.60 11.24 1.546
2 A' A'   2938 3000 -62.1 0.979   1.106 1.107 -0.001 0.999   73.57 35.04 38.52 2.099
3 A' A'   2910 2966 -56.1 0.981   1.077 1.096 -0.019 0.983   72.39 30.76 41.63 2.353
4 A' A'   2890 2942 -51.8 0.982   1.082 1.065 0.017 1.016   12.63 18.80 -6.17 0.672
5 A' A'   2864 2908 -43.8 0.985   1.070 1.066 0.004 1.004   36.66 22.06 14.60 1.662
6 A' A'   1664 1596 68.1 1.043   5.972 5.665 0.307 1.054   1.32 0.70 0.62 1.894
7 A' A'   1494 1480 13.9 1.009   1.109 1.110 -0.002 0.998   0.16 0.83 -0.68 0.187
8 A' A'   1466 1457 8.9 1.006   1.087 1.090 -0.003 0.997   0.68 2.01 -1.33 0.340
9 A' A'   1329 1294 34.7 1.027   1.655 1.738 -0.083 0.952   0.04 0.67 -0.63 0.058
10 A' A'   1216 1199 17.0 1.014   1.215 1.232 -0.017 0.987   1.62 1.38 0.24 1.178
11 A' A'   1108 1092 16.3 1.015   1.095 1.094 0.000 1.000   0.06 0.16 -0.11 0.345
12 A' A'   1063 1042 20.6 1.020   1.702 1.708 -0.006 0.997   10.01 5.21 4.80 1.922
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.