. Author manuscript; available in PMC: 2011 Jul 15.

Published in final edited form as: J Phys Chem B. 2010 Jul 15;114(27):9023–9030. doi: 10.1021/jp102225e

Table 2.

Energy barriers (in kcal/mol) in the gas phase with zero-point corrections calculated for the first step of nicotine C_α-H hydroxylation using different functional with B2 basis set.

	(a) 5′-hydroxylation		(b) N-methylhydroxylation		Barrier difference^a

	HS	LS	HS	LS
BP86	15.4	17.0	18.9	21.0	3.5
BLYP	18.8	20.2	21.6	23.3	2.8
B3LYP*	20.9	23.5	23.6	26.5	2.7
B3LYP	22.2	23.5	24.9	26.6	2.7
B3PW91	20.0	22.6	23.2	26.1	3.2

The difference between the lowest barriers calculated for the two reaction pathways.