National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
VII	Tutorials and Units
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
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XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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

Compare vibrational frequencies for two calculations for FClO (chlorosyl fluoride)

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'		906	1191	-284.9	0.761		19.231	19.503	-0.272	0.986		69.72	47.63	22.09	1.464
2	A'	A'		743	531	211.8	1.399		22.979	22.840	0.139	1.006		146.46	109.79	36.67	1.334
3	A'	A'		327	278	49.3	1.177		19.285	19.145	0.140	1.007		19.02	12.42	6.60	1.531
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.