Abstract
Mixed quantum mechanical/molecular mechanical (QM/MM) models, in which
one part of a system is treated at an ab initio level
while the rest is described by an empirical force field, are becoming
increasingly popular. In this letter, we describe a simple QM/MM
model for methanol (CH3OH) in which the OH constitutes the
ab initio
region and is treated within a density functional representation,
while the methyl group, the MM region, is treated using the AMBER force field. The model
is used to study the structure of the bulk liquid and is shown to
compare favorably with the experimental structure.