Abstract :
The synthesis of single crystalline and polycrystalline
material is reported in the system ZnO1 – xSx.
Substitution of oxygen by sulphur yields hexagonal
wurtzite-type mixed crystals in the range 0 £ x £ 0.05.
The cubic zincblende structure is observed for oxygen
incorporation into ZnS for 0.96 £ x £ 1. At intermediate
compositions, the system is two-phase. For both
types of anion substitution, the band gap energies, as
determined from optical transmission and remission
experiments, are found to decrease from the pure end
members. Quantum chemical calculations at density
functional level identify local structural changes as the
main factor responsible for the reduction of band gap
energies.
