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
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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 C₆F₆ (hexafluorobenzene)

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	A1g	A1g		1507	1460	46.9	1.032		12.833	12.807	0.026	1.002		0.00	0.00	0.00
2	A1g	A1g		550	534	15.3	1.029		17.228	17.274	-0.047	0.997		0.00	0.00	0.00
3	A2g	A2g		769	731	38.6	1.053		12.663	12.657	0.006	1.000		0.00	0.00	0.00
4	A2u	A2u		219	201	18.5	1.092		13.996	13.996	0.000	1.000		12.17	6.09	6.08	1.999
5	B1u	B1u		1336	1283	52.4	1.041		12.759	12.847	-0.088	0.993		0.00	0.00	0.00
6	B1u	B1u		575	564	11.0	1.019		17.364	17.204	0.160	1.009		0.00	0.00	0.00
7	B2g	B2g		606	195	410.8	3.103		12.086	18.576	-6.491	0.651		0.00	0.00	0.00
8	B2g	B2g		182	222i	404.0	-0.821		18.788	12.175	6.613	1.543		0.00	0.00	0.00
9	B2u	B2u		1084	1365	-281.5	0.794		12.004	12.001	0.003	1.000		0.00	0.00	0.00
10	B2u	B2u		264	249	14.5	1.058		18.989	18.997	-0.008	1.000		0.00	0.00	0.00
11	E1g	E1g		392	347	44.5	1.128		12.663	12.657	0.006	1.000		0.00	0.00	0.00
12	E1g	E1g		392	347	44.5	1.128		12.663	12.657	0.006	1.000		0.00	0.00	0.00
13	E1u	E1u		1543	1495	48.6	1.032		12.363	12.352	0.011	1.001		390.03	310.26	79.77	1.257
14	E1u	E1u		1543	1495	48.6	1.032		12.363	12.352	0.011	1.001		390.03	310.26	79.77	1.257
15	E1u	E1u		998	966	32.6	1.034		14.226	14.243	-0.017	0.999		276.90	209.48	67.42	1.322
16	E1u	E1u		998	966	32.6	1.034		14.226	14.243	-0.017	0.999		276.90	209.48	67.42	1.322
17	E1u	E1u		306	292	13.5	1.046		17.781	17.779	0.002	1.000		2.71	1.66	1.04	1.628
18	E1u	E1u		306	292	13.5	1.046		17.781	17.779	0.002	1.000		2.71	1.66	1.04	1.628
19	E2g	E2g		1670	1618	52.0	1.032		12.056	12.051	0.005	1.000		0.00	0.00	0.00
20	E2g	E2g		1670	1618	52.0	1.032		12.056	12.051	0.005	1.000		0.00	0.00	0.00
21	E2g	E2g		1163	1127	35.8	1.032		13.695	13.699	-0.005	1.000		0.00	0.00	0.00
22	E2g	E2g		1163	1127	35.8	1.032		13.695	13.699	-0.005	1.000		0.00	0.00	0.00
23	E2g	E2g		434	419	14.5	1.035		16.060	16.089	-0.029	0.998		0.00	0.00	0.00
24	E2g	E2g		434	419	14.5	1.035		16.060	16.089	-0.029	0.998		0.00	0.00	0.00
25	E2g	E2g		258	241	16.7	1.069		18.622	18.585	0.036	1.002		0.00	0.00	0.00
26	E2g	E2g		258	241	16.7	1.069		18.622	18.585	0.036	1.002		0.00	0.00	0.00
27	E2u	E2u		627	533	93.2	1.175		12.198	12.223	-0.025	0.998		0.00	0.00	0.00
28	E2u	E2u		627	533	93.2	1.175		12.198	12.223	-0.025	0.998		0.00	0.00	0.00
29	E2u	E2u		137	128	8.6	1.068		18.524	18.466	0.057	1.003		0.00	0.00	0.00
30	E2u	E2u		137	128	8.6	1.068		18.524	18.466	0.057	1.003		0.00	0.00	0.00
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.