Polymorphism, band-structure, band-lineup, and alloy energetics of the group II oxides and sulfides MgO, ZnO, CdO, MgS, ZnS, CdS

Abstract

The group II chalcogenides are an important class of functional semiconductor materials exhibiting a remarkable diversity in terms of structure and properties. In order to aid the materials design, a consistent set of electronic structure calculations is presented, including data on the polymorphic energy ordering, the band-structures, the band-lineups relative to the vacuum level, surface energies, as well as on the alloy energetics. To this end, current state-of-the-art electronic structure tools are employed, which, besides standard density functional theory (DFT), include totalenergy calculation in the random phase approximation and GW quasiparticle energy calculations. The ionization potentials and electron affinities are obtained by combining the results of bulk GW and surface DFT calculations. Considering both octahedral and tetrahedral coordination symmetries, exemplified by the rock-salt and zinc-blende lattices, respectively, this data reveals both the chemical and structural trends within this materials family.