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

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at ROHF/6-31G*

Scale factor	How many		Source
	Molecules	Vibrations
0.895 ±

Jump to histogram

Formula	Name	Mode	Symmetry	Frequency			Count
				Theory	Experiment	ratio	molecules	vibrations
CF3	Trifluoromethyl radical	1	A1	1220	1089	0.892	1	1
		2	A1	759	701	0.924	1	2
		3	E	1442	1260	0.874	1	3
		4	E	550	509	0.924	1	4
HCO	Formyl radical	1	A'	3010	2434	0.809	2	5
		2	A'	2155	1868	0.867	2	6
		3	A'	1273	1081	0.849	2	7
C3H3	Propargyl radical	1	A1	3664	3322	0.907	3	8
		6	B1	755	687	0.911	3	9
		7	B1	483	490	1.014	3	10
CH	Methylidyne	1	Σ	3066	2861	0.933	4	11
		1	Σ	3066	3145	1.026	4	12
		1	Σ	3066	2931	0.956	4	13
OH	Hydroxyl radical	1	Σ	4013	3738	0.931	5	14
NF2	Difluoroamino radical	1	A1	1270	1075	0.846	6	15
		2	A1	653	573	0.877	6	16
		3	B2	1193	942	0.790	6	17
CF	Fluoromethylidyne	1	Σ	1410	1308	0.927	7	18
CCl	carbon monochloride	1	Σ	872	877	1.006	8	19
OClO	Chlorine dioxide	1	A1	1070	946	0.883	9	20
		2	A1	508	448	0.882	9	21
		3	B2	1275	1110	0.870	9	22
SiF	silicon monofluoride	1	Σ	919	857	0.932	10	23
SiN	Silicon nitride	1	Σ	1319	1151	0.873	11	24
LiO	lithium oxide	1	Σ	888	815	0.917	12	25
BS	boron sulfide	1	Σ	1269	1180	0.930	13	26
AlS	Aluminum sulfide	1	Σ	681	617	0.906	14	27
CP	Carbon monophosphide	1	Σ	1453	1240	0.853	15	28
NaO	sodium monoxide	1	Σ	525	492	0.938	16	29
Si2	Silicon diatomic	1	Σg	594	511	0.861	17	30
BeF	Beryllium monofluoride	1	Σ	1318	1247	0.947	18	31
PH2	Phosphino radical	1	A1	2582	2310	0.895	19	32
		2	A1	1258	1102	0.876	19	33
SiH3	silyl	1	A1	2362	2136	0.904	20	34
		2	A1	899	728	0.809	20	35
		3	E	2381	2185	0.918	20	36
		4	E	1017	922	0.907	20	37
NH2	Amino radical	1	A1	3623	3219	0.888	21	38
		2	A1	1715	1497	0.873	21	39
		3	B2	3725	3301	0.886	21	40
NH	Imidogen	1	Σ	3568	3283	0.920	22	41
		1	Σ	3568	3314	0.929	22	42
SiH	Silylidyne	1	Σ	2182	2043	0.936	23	43
BeCl	beryllium chloride	1	Σ	856	847	0.990	24	44
SH	Mercapto radical	1	Σ	2899	2696	0.930	25	45
SiCl	Clorosilylidyne	1	Σ	532	536	1.008	26	46
PH	phosphorus monohydride	1	Σ	2551	2364	0.927	27	47
		1	Σ	2551	2415	0.947	27	48
		1	Σ	2551	2403	0.942	27	49
MgH	magnesium monohydride	1	Σ	1577	1493	0.947	28	50
BH2	boron dihydride	2	A1	1150	954	0.829	29	51
AlH2	aluminum dihydride	1	A1	1970	1770	0.899	30	52
		2	A1	821	760	0.926	30	53
		3	B2	1984	1807	0.911	30	54
MgF	Magnesium monofluoride	1	Σ	779	712	0.914	31	55
MgCl	magnesium monochloride	1	Σ	459	462	1.006	32	56
ClO	Monochlorine monoxide	1	Σ	869	854	0.982	33	57
PF	phosphorus monofluoride	1	Σ	912	847	0.929	34	58
BeOH	beryllium hydroxide	2	A'	1303	1246	0.956	35	59
S2	Sulfur diatomic	1	Σg	819	726	0.887	36	60
ClS2	Sulfur chloride	1	A'	598	662	1.106	37	61
		2	A'	528	450	0.852	37	62
		3	A'	241	196	0.812	37	63

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.

	25
	20
	15
	10
	5
	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