III.B.3.b. (XIII.C.2.)

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at CID/3-21G*

Scale factor	How many		Source
	Molecules	Vibrations
0.931 ± 0.025	11	171	cccbdb

Jump to histogram

Formula	Name	Mode	Symmetry	Frequency			Count
				Theory	Experiment	ratio	molecules	vibrations
CH3CH2NH2	Ethylamine	1	A'	3476	3345	0.962	1	1
		2	A'	3162	2985	0.944	1	2
		3	A'	3116	2840	0.912	1	3
		4	A'	3092	2860	0.925	1	4
		5	A'	1784	1622	0.909	1	5
		6	A'	1610	1487	0.924	1	6
		7	A'	1595	1465	0.919	1	7
		8	A'	1500	1378	0.918	1	8
		9	A'	1445	1397	0.967	1	9
		10	A'	1196	1016	0.850	1	10
		11	A'	1053	1086	1.032	1	11
		12	A'	917	892	0.973	1	12
		13	A'	810	773	0.954	1	13
		14	A'	404	403	0.997	1	14
		15	A"	3568	3412	0.956	1	15
		16	A"	3168	2924	0.923	1	16
		17	A"	3141	2906	0.925	1	17
		18	A"	1607	1455	0.906	1	18
		19	A"	1447	1238	0.856	1	19
		20	A"	1345	1293	0.961	1	20
		21	A"	1055	1117	1.059	1	21
		22	A"	808	816	1.010	1	22
		23	A"	315	259	0.822	1	23
		24	A"	262	218	0.831	1	24
CH3COOCH3	methyl acetate	1	A'	3254	3035	0.933	2	25
		2	A'	3253	3031	0.932	2	26
		3	A'	3154	2966	0.940	2	27
		4	A'	3149	2964	0.941	2	28
		5	A'	1857	1771	0.954	2	29
		6	A'	1625	1460	0.899	2	30
		7	A'	1589	1440	0.906	2	31
		8	A'	1559	1430	0.917	2	32
		9	A'	1505	1375	0.914	2	33
		10	A'	1319	1248	0.946	2	34
		11	A'	1245	1159	0.931	2	35
		12	A'	1130	1060	0.938	2	36
		13	A'	1019	980	0.962	2	37
		14	A'	853	844	0.989	2	38
		15	A'	657	639	0.973	2	39
		16	A'	419	429	1.024	2	40
		17	A'	277	303	1.095	2	41
		18	A"	3216	3005	0.934	2	42
		19	A"	3214	2994	0.932	2	43
		20	A"	1609	1460	0.907	2	44
		21	A"	1596	1430	0.896	2	45
		22	A"	1222	1187	0.971	2	46
		23	A"	1152	1036	0.899	2	47
		24	A"	619	607	0.980	2	48
		25	A"	174	187	1.076	2	49
		26	A"	119	136	1.144	2	50
		27	A"	108	110	1.021	2	51
CH2CHCH3	Propene	1	A'	3269	3090	0.945	3	52
		2	A'	3201	3013	0.941	3	53
		3	A'	3187	2991	0.938	3	54
		4	A'	3159	2954	0.935	3	55
		5	A'	3090	2871	0.929	3	56
		6	A'	1761	1650	0.937	3	57
		7	A'	1606	1470	0.915	3	58
		8	A'	1545	1420	0.919	3	59
		9	A'	1509	1378	0.913	3	60
		10	A'	1403	1297	0.924	3	61
		11	A'	1250	1171	0.937	3	62
		12	A'	1021	963	0.944	3	63
		13	A'	920	920	1.000	3	64
		14	A'	450	428	0.952	3	65
		15	A"	3142	2954	0.940	3	66
		16	A"	1593	1443	0.906	3	67
		17	A"	1148	1045	0.910	3	68
		18	A"	1066	991	0.930	3	69
		19	A"	996	912	0.915	3	70
		20	A"	608	578	0.951	3	71
		21	A"	188	174	0.927	3	72
CH3CH2CHO	Propanal	1	A'	3198	2981	0.932	4	73
		2	A'	3132	2904	0.927	4	74
		3	A'	3109	2895	0.931	4	75
		4	A'	3027	2809	0.928	4	76
		5	A'	1795	1743	0.971	4	77
		6	A'	1612	1460	0.905	4	78
		7	A'	1574	1416	0.899	4	79
		8	A'	1525	1390	0.911	4	80
		9	A'	1497	1376	0.919	4	81
		10	A'	1424	1335	0.938	4	82
		11	A'	1155	1093	0.946	4	83
		12	A'	1044	993	0.951	4	84
		13	A'	865	848	0.981	4	85
		14	A'	704	668	0.949	4	86
		15	A'	281	271	0.964	4	87
		16	A"	3202	2992	0.934	4	88
		17	A"	3137	2942	0.938	4	89
		18	A"	1614	1451	0.899	4	90
		19	A"	1367	1250	0.915	4	91
		20	A"	1222	1118	0.915	4	92
		21	A"	968	892	0.922	4	93
		22	A"	739	660	0.894	4	94
		23	A"	240	220	0.915	4	95
		24	A"	137	135	0.988	4	96
C5H8	1,4-Pentadiene	1	A	3293	3080	0.935	5	97
		2	A	3227	3012	0.933	5	98
		3	A	3211	3012	0.938	5	99
		4	A	3106	2900	0.934	5	100
		5	A	1781	1644	0.923	5	101
		6	A	1586	1433	0.904	5	102
		7	A	1559	1413	0.906	5	103
		8	A	1404	1295	0.922	5	104
		9	A	1342	1263	0.941	5	105
		10	A	1151	1120	0.973	5	106
		11	A	1081	995	0.921	5	107
		12	A	1022	918	0.899	5	108
		13	A	950	876	0.922	5	109
		14	A	704	562	0.799	5	110
		15	A	392	421	1.073	5	111
		16	A	319	137	0.430	5	112
		17	A	86	102	1.189	5	113
		18	B	3293	3080	0.935	5	114
		19	B	3226	3012	0.934	5	115
		20	B	3212	3012	0.938	5	116
		21	B	3147	2982	0.947	5	117
		22	B	1765	1640	0.929	5	118
		23	B	1555	1413	0.909	5	119
		24	B	1407	1314	0.934	5	120
		25	B	1394	1280	0.918	5	121
		26	B	1229	1060	0.863	5	122
		27	B	1082	995	0.920	5	123
		28	B	1020	995	0.975	5	124
		29	B	986	920	0.933	5	125
		30	B	947	760	0.803	5	126
		31	B	637	721	1.132	5	127
		32	B	474	421	0.887	5	128
		33	B	90	331	3.667	5	129
CH3SSCH3	Disulfide, dimethyl	1	A	3229	2990	0.926	6	130
		2	A	3211	2983	0.929	6	131
		3	A	3135	2913	0.929	6	132
		4	A	1597	1426	0.893	6	133
		5	A	1588	1419	0.894	6	134
		6	A	1484	1311	0.883	6	135
		7	A	1064	955	0.898	6	136
		8	A	1061	949	0.895	6	137
		9	A	723	694	0.959	6	138
		10	A	534	509	0.953	6	139
		11	A	249	240	0.964	6	140
		12	A	157	134	0.855	6	141
		13	A	107	117	1.097	6	142
		14	B	3228	2990	0.926	6	143
		15	B	3210	2983	0.929	6	144
		16	B	3132	2915	0.931	6	145
		17	B	1601	1430	0.893	6	146
		18	B	1582	1415	0.895	6	147
		19	B	1477	1303	0.882	6	148
		20	B	1069	955	0.894	6	149
		21	B	1055	949	0.899	6	150
		22	B	718	691	0.963	6	151
		23	B	285	274	0.961	6	152
		24	B	168	134	0.797	6	153
SF6	Sulfur Hexafluoride	1	A1g	868	774	0.891	7	154
		2	Eg	778	642	0.825	7	155
		3	T1u	1155	948	0.821	7	156
		4	T1u	638	616	0.965	7	157
		5	T2g	542	525	0.969	7	158
		6	T2u	368	347	0.944	7	159
CS	carbon monosulfide	1	Σ	1356	1285	0.948	8	160
SiH2Cl2	dichlorosilane	1	A1	2409	2224	0.923	9	161
		2	A1	1010	954	0.944	9	162
		3	A1	559	527	0.942	9	163
		4	A1	200	188	0.939	9	164
		5	A2	772	710	0.920	9	165
		6	B1	2421	2237	0.924	9	166
		7	B1	631	602	0.954	9	167
		8	B2	948	876	0.924	9	168
		9	B2	630	590	0.937	9	169
LiO	lithium oxide	1	Σ	902	815	0.903	10	170
NaO	sodium monoxide	1	Σ	547	492	0.900	11	171

How do we calculate the scaling factor?

Histogram of vibrational frequency ratios

Ratios greater than 1.35 are in the 1.35 bin. Ratios less than 0.7 are in the 0.7 bin.

	80
	70
	60
	50
	40
	30
	20
	10
	0
		0.70			0.75			0.80			0.85			0.90			0.95			1.00			1.05			1.10			1.15			1.20			1.25			1.30			1.35
Ratio of experimental frequency to calculated frequency