Predictions and systematizations of the zinc-blende–wurtzite structural energies in binary octet compounds

Abstract

To systematize the wurtzite (W) versus zinc blende (ZB) structural preferences among the binary octet compounds, we have calculated the correponding energy difference \ensuremath{\Delta}${\mathit{E}}_{\mathit{W}\mathrm{\ensuremath{-}}\mathrm{ZB}}^{\mathrm{LDF}}$(AB) for thirteen AB compounds using the local-density formalism (LDF). We then uncovered a linear scaling betwteen \ensuremath{\Delta}${\mathit{E}}_{\mathit{W}\mathrm{\ensuremath{-}}\mathrm{ZB}}^{\mathrm{LDF}}$ and an atomistic orbital-radii coordinate R\ifmmode \tilde{}\else \~{}\fi{}(A,B) that can be simply calculated from the properties of the free A and B atoms. This permits predictions of W-ZB energy differences for all binary compounds and exposes simple chemical trends, including the stabilization of the ZB form in the sequence B=O\ensuremath{\rightarrow}S\ensuremath{\rightarrow}Se\ensuremath{\rightarrow}Te for ${\mathit{A}}^{\mathrm{II}}$${\mathit{B}}^{\mathrm{VI}}$ and A=Ga\ensuremath{\rightarrow}Al\ensuremath{\rightarrow}In for ${\mathit{A}}^{\mathrm{III}}$${\mathit{B}}^{\mathrm{V}}$'s. We propose new structural assignments for the low-temperature ground state of CdSe (ZB) and MgTe (NiAs type).