ABSTRACT
Quantum mechanics is the bedrock upon which multi-scale models
are built. For decades, it has been a source of parameters for
force-field models, which are vastly less computationally expensive
and hence able to reach much longer length and time scales.
It is also being increasingly used in concert with force-field
methods through mixed quantum mechanics/molecular mechanics
(QM/MM) approaches, which have the advantage of accuracy (QM)
in the critical region of interest and efficiency (MM) in the less
important regions.