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
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

return to home page

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

Compare vibrational frequencies for two calculations for HCNH (HCNH)

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'   3219 3248 -28.5 0.991   1.075 1.100 -0.026 0.977   2.51 18.07 -15.57 0.139
2 A' A'   2919 2885 34.2 1.012   1.088 1.261 -0.173 0.863   33.03 323.74 -290.71 0.102
3 A' A'   1497 2339 -841.4 0.640   6.433 3.742 2.691 1.719   0.67 390.15 -389.47 0.002
4 A' A'   1137 985 151.9 1.154   1.474 1.256 0.219 1.174   116.70 89.89 26.81 1.298
5 A' A'   910 699 210.3 1.301   1.045 1.172 -0.126 0.892   45.48 332.42 -286.94 0.137
6 A" A"   955 896 59.9 1.067   1.285 1.335 -0.050 0.962   8.56 12.02 -3.45 0.713
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.