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

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at CCSD(T)=FULL/cc-pCVTZ

Scale factor	How many		Source
	Molecules	Vibrations
0.966 ± 0.019	47	122	cccbdb

Jump to histogram

Formula	Name	Mode	Symmetry	Frequency			Count
				Theory	Experiment	ratio	molecules	vibrations
H2CO	Formaldehyde	1	A1	2932	2782	0.949	1	1
		2	A1	1786	1746	0.977	1	2
		3	A1	1545	1500	0.971	1	3
		4	B1	1194	1167	0.977	1	4
		5	B2	2999	2843	0.948	1	5
		6	B2	1277	1249	0.978	1	6
CH4	Methane	1	A1	3040	2917	0.959	2	7
		2	E	1572	1534	0.976	2	8
		3	T2	3161	3019	0.955	2	9
		4	T2	1345	1306	0.971	2	10
C2H4	Ethylene	1	Ag	3161	3026	0.957	3	11
		2	Ag	1676	1623	0.968	3	12
		3	Ag	1372	1342	0.979	3	13
		4	Au	1050	1023	0.975	3	14
		5	B1u	3145	2989	0.950	3	15
		6	B1u	1480	1444	0.975	3	16
		7	B2g	947	940	0.992	3	17
		8	B2u	3253	3105	0.954	3	18
		9	B2u	823	826	1.003	3	19
		10	B3g	3227	3086	0.956	3	20
		11	B3g	1244	1217	0.979	3	21
		12	B3u	969	949	0.979	3	22
C2H2	Acetylene	1	Σg	3506	3374	0.962	4	23
		2	Σg	2009	1974	0.983	4	24
		3	Σu	3415	3289	0.963	4	25
		4	Πg	587	612	1.042	4	26
		5	Πu	748	730	0.976	4	27
HCN	Hydrogen cyanide	1	Σ	3440	3312	0.963	5	28
		2	Σ	2123	2089	0.984	5	29
		3	Π	723	712	0.984	5	30
CS2	Carbon disulfide	1	Σg	671	658	0.981	6	31
		2	Σu	1564	1535	0.981	6	32
		3	Πu	403	397	0.984	6	33
CO2	Carbon dioxide	1	Σg	1352	1333	0.986	7	34
		2	Σu	2400	2349	0.979	7	35
		3	Πu	667	667	1.000	7	36
ClCN	chlorocyanogen	1	Σ	2251	2216	0.984	8	37
		2	Σ	745	744	0.999	8	38
		3	Π	387	378	0.976	8	39
CO	Carbon monoxide	1	Σ	2163	2170	1.003	9	40
		1	Σ	2163	1743	0.806	9	41
H2CS	Thioformaldehyde	1	A1	3090	2971	0.961	10	42
		2	A1	1503	1456	0.969	10	43
		3	A1	1073	1059	0.987	10	44
		4	B1	1010	990	0.980	10	45
		5	B2	3181	3025	0.951	10	46
		6	B2	1005	991	0.986	10	47
MgO	magnesium oxide	1	Σ	809	785	0.970	11	48
CN	Cyano radical	1	Σ	2126	2069	0.973	12	49
CCH2	vinylidene	1	A1	3134	3025	0.965	13	50
		2	A1	1670	1635	0.979	13	51
		3	A1	1227	1165	0.949	13	52
OH	Hydroxyl radical	1	Σ	3738	3738	1.000	14	53
CF	Fluoromethylidyne	1	Σ	1326	1308	0.986	15	54
SO2	Sulfur dioxide	1	A1	1172	1151	0.982	16	55
		2	A1	520	518	0.996	16	56
		3	B2	1391	1362	0.979	16	57
LiH	Lithium Hydride	1	Σ	1400	1405	1.004	17	58
HCl	Hydrogen chloride	1	Σ	3013	2991	0.993	18	59
HF	Hydrogen fluoride	1	Σ	4182	4138	0.990	19	60
NH3	Ammonia	1	A1	3479	3337	0.959	20	61
		2	A1	1106	950	0.859	20	62
		3	E	3604	3444	0.956	20	63
		4	E	1689	1627	0.963	20	64
H2O2	Hydrogen peroxide	1	A	3809	3599	0.945	21	65
		2	A	1439	1402	0.974	21	66
		3	A	916	877	0.958	21	67
		4	A	364	371	1.019	21	68
		5	B	3808	3608	0.948	21	69
		6	B	1326	1266	0.954	21	70
N2	Nitrogen diatomic	1	Σg	2354	2359	1.002	22	71
H2O	Water	1	A1	3842	3657	0.952	23	72
		2	A1	1667	1595	0.957	23	73
		3	B2	3945	3756	0.952	23	74
F2	Fluorine diatomic	1	Σg	925	917	0.991	24	75
O2	Oxygen diatomic	1	Σg	1590	1580	0.994	25	76
		1	Σg	1590	1484	0.933	25	77
		1	Σg	1590	1433	0.901	25	78
		1	Σg	1590	794	0.500	25	79
Cl2	Chlorine diatomic	1	Σg	552	560	1.014	26	80
H2S	Hydrogen sulfide	1	A1	2732	2615	0.957	27	81
		2	A1	1211	1183	0.977	27	82
		3	B2	2749	2626	0.955	27	83
AlH3	aluminum trihydride	1	A1'	1946	1900	0.977	28	84
		2	A2"	717	698	0.973	28	85
		3	E'	1951	1883	0.965	28	86
		4	E'	796	783	0.984	28	87
FNO	Nitrosyl fluoride	1	A'	1856	1844	0.994	29	88
		2	A'	805	766	0.951	29	89
		3	A'	551	520	0.944	29	90
ClF	Chlorine monofluoride	1	Σ	778	783	1.007	30	91
PH3	Phosphine	1	A1	2423	2323	0.959	31	92
		2	A1	1024	992	0.969	31	93
		3	E	2433	2328	0.957	31	94
		4	E	1148	1118	0.974	31	95
SiH4	Silane	1	A1	2261	2187	0.967	32	96
		2	E	993	975	0.982	32	97
		3	T2	2269	2191	0.966	32	98
		4	T2	937	914	0.975	32	99
N2O	Nitrous oxide	1	Σ	2291	2224	0.971	33	100
		2	Σ	1305	1285	0.985	33	101
		3	Π	606	589	0.972	33	102
O3	Ozone	1	A1	1158	1110	0.959	34	103
		2	A1	720	705	0.980	34	104
		3	B2	1062	1042	0.982	34	105
SiO	Silicon monoxide	1	Σ	1235	1242	1.005	35	106
NO	Nitric oxide	1	Σ	2104	1904	0.905	36	107
BCl3	Borane, trichloro-	1	A1'	479	471	0.984	37	108
		2	A2"	465	460	0.990	37	109
		3	E'	975	956	0.980	37	110
		4	E'	258	243	0.942	37	111
C2	Carbon diatomic	1	Σg	1856	1855	0.999	38	112
		1	Σg	1639	1855	1.132	38	113
P2	Phosphorus diatomic	1	Σg	777	781	1.004	39	114
AlF	Aluminum monofluoride	1	Σ	795	802	1.009	40	115
BF	Boron monofluoride	1	Σ	1411	1402	0.993	41	116
SiH	Silylidyne	1	Σ	2036	2043	1.003	42	117
SO	Sulfur monoxide	1	Σ	1156	1151	0.995	43	118
NF	nitrogen fluoride	1	Σ	1156	1141	0.987	44	119
ClO	Monochlorine monoxide	1	Σ	843	854	1.012	45	120
N2H2	trans-diazine	1	Ag	3268	3128	0.957	46	121
		2	Ag	1623	1583	0.976	46	122
		3	Ag	1564	1529	0.978	46	123
		4	Au	1331	1289	0.968	46	124
		5	Bu	3301	3120	0.945	46	125
		6	Bu	1352	1316	0.974	46	126
S2	Sulfur diatomic	1	Σg	721	726	1.007	47	127

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.

	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