Table 9.

Computed harmonic ω and experimental and calculated anharmonic fundamental wavenumbers ν for benzene (in cm⁻¹)

		B3LYP/SNSD					HYBRID					Expt.
State	Symm.	ω					ω					ν
		1011	997	997	997	997	1003	989	989	989	989	993
		3195	3054	3055	3055	3054	*3210	3069	3070	3070	3073	3074
		1375	1349	1349	1349	1349	*1380	1348	1351	1351	1350	(1350)
		717	692	692	692	692	709	684	684	684	684	(707)
		1015	980	980	980	980	1009	974	974	974	974	(990)
		864	842	842	842	842	865	843	843	843	843	847
		616	612	612	612	612	611	607	607	607	607	608
		1193	1179	1179	1179	1179	1194	1179	1179	1179	1179	1178
		*1635	1604	1599	1599	1588	1637	1598	1598	1598	1598	1601
		3169	3008	3008	3008	3008	3183	3023	3022	3022	3023	3057
		688	673	673	673	673	687	673	673	673	673	674
		1013	1009	1009	1009	1009	1020	1016	1016	1016	1016	(1010)
		*3159	3143	3069	3069	2996	*3173	3105	3076	3076	3009	(3057)
		1169	1158	1158	1158	1158	1163	1152	1152	1152	1152	1150
		1349	1323	1323	1323	1323	1326	1304	1302	1302	1304	1309
		1056	1038	1038	1038	1038	1056	1038	1038	1038	1038	1038
		1509	1479	1479	1479	1479	1509	1479	1479	1479	1479	1484
		*3185	3073	3067	3069	3029	*3200	3083	3080	3081	3040	3047
		411	402	402	402	402	406	397	397	397	397	398
		987	968	968	968	968	985	966	966	966	966	976
MAE			13	9	9	12		10	9	9	9

The vibrational states are indicated as. In the hybrid method, the harmonic frequencies are calculated at the CCSD(T)/ANO4321′ level, from Table 1 of Ref.175, and the anharmonic force field at the B3LYP/SNSD one.

The experimental values are from Ref.38.

The values in parentheses have not been observed directly but have been deduced from combination bands.

The frequencies treated as resonant (DVPT2/GVPT2) are indicated with a ^*.

MAE stands for Mean Absolute Error.