Chemical classification
Solids are often classified according to their chemical bonding, structures and properties (see Topic B1):
Molecular solids contain discrete molecular units held by relatively weak intermolecular forces (see
Topic C10).
Metallic solids have atoms with high coordination numbers, bound by delocalized electrons that give metallic
conduction.
Covalent or polymeric solids have atoms bound by directional covalent bonds, giving relatively low
coordination numbers in a continuous one-, two- or three-dimensional network.