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

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at ROHF/cc-pVTZ

Scale factor	How many		Source
	Molecules	Vibrations
0.901 ± 0.080	60	159	cccbdb

Jump to histogram

Formula	Name	Mode	Symmetry	Frequency			Count
				Theory	Experiment	ratio	molecules	vibrations
C3H7	Isopropyl radical	1	A'	3283	3052	0.930	1	1
		2	A'	3212	3052	0.950	1	2
		3	A'	3176	2920	0.919	1	3
		4	A'	3115	2850	0.915	1	4
		5	A'	1608	1468	0.913	1	5
		6	A'	1605	1440	0.897	1	6
		8	A'	1277	1165	0.912	1	7
		10	A'	923	879	0.952	1	8
		12	A'	381	364	0.956	1	9
		14	A"	3213	2920	0.909	1	10
		15	A"	3172	2920	0.920	1	11
		16	A"	3111	2830	0.910	1	12
		19	A"	1538	1388	0.902	1	13
		20	A"	1474	1378	0.935	1	14
C2H5	Ethyl radical	14	A'	3271	3033	0.927	2	15
		12	A'	3183	2842	0.893	2	16
		8	A'	1588	1440	0.907	2	17
		7	A'	1527	1366	0.895	2	18
		5	A'	1106	1138	1.029	2	19
		2	A'	529	528	0.999	2	20
		15	A"	3367	3112	0.924	2	21
		13	A"	3214	2987	0.929	2	22
		10	A"	1604	1440	0.898	2	23
		6	A"	1302	1175	0.903	2	24
CN	Cyano radical	1	Σ	2451	2069	0.844	3	25
C2H	Ethynyl radical	1	Σ	3621	3299	0.911	4	26
		2	Σ	2281	1841	0.807	4	27
		3	Π	751	372	0.495	4	28
CH3	Methyl radical	1	A1'	3246	3004	0.926	5	29
		2	A2"	174	606	3.485	5	30
		3	E'	3423	3161	0.923	5	31
		4	E'	1522	1396	0.917	5	32
CF3	Trifluoromethyl radical	1	A1	1221	1089	0.892	6	33
		2	A1	772	701	0.909	6	34
		3	E	1424	1260	0.885	6	35
		4	E	562	509	0.906	6	36
C6H5	phenyl	1	A1	3349	3086	0.922	7	37
		2	A1	3336	3072	0.921	7	38
		3	A1	3311	3037	0.917	7	39
		4	A1	1734	1497	0.864	7	40
		5	A1	1610	1439	0.894	7	41
		6	A1	1264	1151	0.911	7	42
		7	A1	1118	1028	0.919	7	43
		8	A1	1079	998	0.925	7	44
		9	A1	1070	973	0.910	7	45
		10	A1	661	605	0.916	7	46
		11	A2	1093	945	0.864	7	47
		12	A2	933	816	0.874	7	48
		13	A2	449			7	49
		14	B1	1116	990	0.887	7	50
		15	B1	1000	873	0.873	7	51
		16	B1	801	703	0.877	7	52
		17	B1	745	655	0.879	7	53
		18	B1	470	415	0.883	7	54
		19	B2	3344	3070	0.918	7	55
		20	B2	3321	3060	0.921	7	56
		21	B2	1767	1593	0.902	7	57
		22	B2	1581	1432	0.906	7	58
		23	B2	1418	1310	0.924	7	59
		24	B2	1325	1281	0.967	7	60
		25	B2	1199	1159	0.967	7	61
		26	B2	1132	1060	0.936	7	62
		27	B2	650	588	0.904	7	63
CH2	Methylene	1	A1	3259	2806	0.861	8	64
		2	A1	1300	963	0.741	8	65
		3	B2	3468	3190	0.920	8	66
		1	A1	3259	2806	0.861	8	67
		2	A1	1300	1353	1.041	8	68
		3	B2	3468	2865	0.826	8	69
CH2OH	Hydroxymethyl radical	1	A	4176	3650	0.874	9	70
		4	A	1607	1459	0.908	9	71
		5	A	1469	1334	0.908	9	72
		6	A	1274	1176	0.923	9	73
		7	A	1150	1048	0.912	9	74
		8	A	884	482	0.545	9	75
		9	A	400	234	0.585	9	76
HCO	Formyl radical	1	A'	2944	2434	0.827	10	77
		2	A'	2131	1868	0.877	10	78
		3	A'	1250	1081	0.865	10	79
C2H3	vinyl	1	A'	3376	3141	0.930	11	80
		2	A'	3333	2953	0.886	11	81
		3	A'	3249	2912	0.896	11	82
		5	A'	1508	1360	0.902	11	83
		7	A'	826	674	0.816	11	84
		8	A"	1057	895	0.847	11	85
		9	A"	966	857	0.887	11	86
C3H3	Propargyl radical	1	A1	3620	3322	0.918	12	87
		6	B1	764	687	0.899	12	88
		7	B1	507	490	0.966	12	89
HO2	Hydroperoxy radical	1	A'	4070	3436	0.844	13	90
		2	A'	1607	1392	0.866	13	91
		3	A'	1251	1098	0.877	13	92
CH	Methylidyne	1	Σ	3035	2861	0.943	14	93
		1	Σ	3035	3145	1.036	14	94
		1	Σ	3035	2931	0.966	14	95
OH	Hydroxyl radical	1	Σ	4053	3738	0.922	15	96
NF2	Difluoroamino radical	1	A1	1271	1075	0.846	16	97
		2	A1	670	573	0.855	16	98
		3	B2	1179	942	0.799	16	99
CF	Fluoromethylidyne	1	Σ	1417	1308	0.923	17	100
CCl	carbon monochloride	1	Σ	867	877	1.011	18	101
O2	Oxygen diatomic	1	Σg	2004	1580	0.788	19	102
		1	Σg	2004	1484	0.740	19	103
		1	Σg	2004	1433	0.715	19	104
		1	Σg	2004	794	0.396	19	105
BN	boron nitride	1	Σ	1778	1520	0.855	20	106
OClO	Chlorine dioxide	1	A1	1138	946	0.831	21	107
		2	A1	543	448	0.824	21	108
		3	B2	1323	1110	0.839	21	109
NO	Nitric oxide	1	Σ	2253	1904	0.845	22	110
NO2	Nitrogen dioxide	1	A1	1622	1318	0.813	23	111
		2	A1	855	750	0.877	23	112
		3	B2	1925	1618	0.841	23	113
SiF	silicon monofluoride	1	Σ	897	857	0.956	24	114
NS	Mononitrogen monosulfide	1	Σ	1343	1219	0.907	25	115
SiN	Silicon nitride	1	Σ	1309	1151	0.880	26	116
FO	Oxygen monofluoride	1	Σ	1246	1053	0.845	27	117
PO2	Phosphorus dioxide	1	A1	1259	1076	0.855	28	118
		2	A1	474	397	0.837	28	119
		3	B2	1565	1328	0.848	28	120
C4	Carbon tetramer	1	Σg	2321	2057	0.886	29	121
		3	Σu	1292	1549	1.199	29	122
		4	Πg	467	323	0.691	29	123
		5	Πu	212	160	0.756	29	124
BS	boron sulfide	1	Σ	1261	1180	0.936	30	125
AlS	Aluminum sulfide	1	Σ	681	617	0.906	31	126
PS	phosphorus sulfide	1	Σ	823	739	0.898	32	127
CP	Carbon monophosphide	1	Σ	1448	1240	0.856	33	128
BO	boron monoxide	1	Σ	2097	1885	0.899	34	129
Si2	Silicon diatomic	1	Σg	593	511	0.862	35	130
SeO	Selenium monoxide	1	Σ	1121	915	0.816	36	131
DO	Hydroxyl-d	1	Σ	2951	2720	0.922	37	132
BeH	beryllium monohydride	1	Σ	2129	2061	0.968	38	133
PH2	Phosphino radical	1	A1	2507	2310	0.921	39	134
		2	A1	1222	1102	0.902	39	135
SiH3	silyl	1	A1	2298	2136	0.929	40	136
		2	A1	903	728	0.806	40	137
		3	E	2314	2185	0.944	40	138
		4	E	1010	922	0.913	40	139
NH2	Amino radical	1	A1	3612	3219	0.891	41	140
		2	A1	1649	1497	0.908	41	141
		3	B2	3700	3301	0.892	41	142
NH	Imidogen	1	Σ	3544	3283	0.926	42	143
		1	Σ	3544	3314	0.935	42	144
SiH	Silylidyne	1	Σ	2119	2043	0.964	43	145
DS	Mercapto-d	1	Σ	2035	1886	0.927	44	146
SO	Sulfur monoxide	1	Σ	1372	1151	0.839	45	147
BO2	Boron dioxide	1	Σg	1193	1278	1.071	46	148
		2	Σu	2694	1056	0.392	46	149
		3	Πu	536	448	0.836	46	150
SH	Mercapto radical	1	Σ	2834	2696	0.952	47	151
HSe	Selenium monohydride	1	Σ	2560	2400	0.937	48	152
SiCl	Clorosilylidyne	1	Σ	528	536	1.015	49	153
NF	nitrogen fluoride	1	Σ	1259	1141	0.906	50	154
PH	phosphorus monohydride	1	Σ	2482	2364	0.952	51	155
		1	Σ	2482	2415	0.973	51	156
		1	Σ	2482	2403	0.968	51	157
BH2	boron dihydride	2	A1	1125	954	0.847	52	158
PO	Phosphorus monoxide	1	Σ	1434	1233	0.860	53	159
AlO	Aluminum monoxide	1	Σ	783	979	1.250	54	160
AlH2	aluminum dihydride	1	A1	1943	1770	0.911	55	161
		2	A1	820	760	0.926	55	162
		3	B2	1953	1807	0.925	55	163
ClO	Monochlorine monoxide	1	Σ	871	854	0.980	56	164
PF	phosphorus monofluoride	1	Σ	903	847	0.938	57	165
ClOO	chloroperoxy radical	1	A'	1198	1443	1.205	58	166
		2	A'	810	414	0.511	58	167
		3	A'	486	201	0.414	58	168
S2	Sulfur diatomic	1	Σg	818	726	0.887	59	169
AlN	Aluminum nitride	1	Σ	719	747	1.039	60	170
ClS2	Sulfur chloride	1	A'	595	662	1.112	61	171
		2	A'	531	450	0.847	61	172
		3	A'	239	196	0.819	61	173

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