Molecular modelling encompasses all theoretical methods and computational techniques used to
model or mimic the behaviour of
molecules. The techniques are used in the fields of
computational chemistry,
drug design,
computational biology and
materials science for studying molecular systems ranging from small chemical systems to large biological molecules and material assemblies. The simplest calculations can be performed by hand, but inevitably computers are required to perform molecular modelling of any reasonably sized system. The common feature of molecular modelling techniques is the atomistic level description of the molecular systems. This may include treating atoms as the smallest individual unit (the
Molecular mechanics approach), or explicitly modeling electrons of each atom (the
quantum chemistry approach).