  Density functional theory based study of the pressure dependent physical
properties of binary SnS compound has been carried out. The computed elastic
constants reveal that SnS is mechanically stable and brittle under ambient
conditions. With increasing pressure, the compound becomes ductile. The
Poisson's ratio also indicates brittle-ductile transition with increasing
pressure. The hardness of SnS increases significantly with pressure. The
compound possesses elastic anisotropy. The ground state electronic band
structure is semiconducting with a small band gap which becomes metallic under
pressure. The band becomes more and more dispersive with the increase in
pressure while the electronic correlations decrease as pressure is raised. Both
the Debye temperature and the phonon thermal conductivity of SnS increase
sharply with pressure. The Melting temperature of the compound is low. Mixed
bonding characteristics are found with ionic and covalent contributions. SnS is
a good absorber of ultraviolet light. The reflectivity of the material
increases with the increase in pressure. The reflectivity is nonselective over
a wide spectral range. The low energy refractive index is high. All these
optical characteristics are useful for prospective optoelectronic device
applications. The optical anisotropy is low.
