National Institute of Standards and Technology

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

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

Compare vibrational frequencies for two calculations for CH₃CHCH (1-propenyl radical)

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'		3080	3145	-65.6	0.979		1.095	1.111	-0.017	0.985		5.48	1.11	4.37	4.933
2	A'	A'		2954	3036	-82.0	0.973		1.101	1.104	-0.003	0.998		39.39	12.72	26.67	3.096
3	A'	A'		2928	2961	-32.5	0.989		1.084	1.084	-0.000	1.000		12.58	10.94	1.64	1.150
4	A'	A'		2873	2932	-58.5	0.980		1.038	1.036	0.002	1.002		36.43	20.36	16.07	1.789
5	A'	A'		1491	1809	-318.6	0.824		1.476	6.837	-5.361	0.216		2.76	3.55	-0.79	0.777
6	A'	A'		1441	1467	-25.6	0.983		1.784	1.049	0.735	1.701		2.82	7.86	-5.04	0.359
7	A'	A'		1403	1384	18.8	1.014		1.237	1.259	-0.022	0.983		1.50	2.30	-0.79	0.654
8	A'	A'		1218	1258	-40.5	0.968		1.470	1.221	0.249	1.204		1.79	1.96	-0.17	0.914
9	A'	A'		1102	1103	-1.4	0.999		1.905	2.045	-0.140	0.932		6.63	7.95	-1.33	0.833
10	A'	A'		898	922	-24.0	0.974		1.568	1.706	-0.139	0.919		0.07	2.71	-2.64	0.025
11	A'	A'		822	816	6.0	1.007		1.493	1.303	0.191	1.146		11.05	16.51	-5.45	0.670
12	A'	A'		399	402	-2.5	0.994		2.362	2.290	0.072	1.032		4.92	7.97	-3.05	0.617
13	A"	A"		2917	3005	-88.1	0.971		1.102	1.102	-0.000	1.000		39.68	17.10	22.58	2.320
14	A"	A"		1463	1460	2.6	1.002		1.046	1.045	0.000	1.000		4.91	7.48	-2.57	0.657
15	A"	A"		1035	1075	-39.9	0.963		1.427	1.548	-0.121	0.922		1.70	2.38	-0.69	0.711
16	A"	A"		805	914	-108.7	0.881		1.269	1.242	0.027	1.022		0.83	7.81	-6.98	0.107
17	A"	A"		577	648	-70.4	0.891		1.141	1.115	0.025	1.023		45.92	59.21	-13.29	0.776
18	A"	A"		165	205	-40.3	0.804		1.248	1.250	-0.002	0.999		0.02	0.01	0.01	3.044
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.