Keywords

ordering, alloys, first-principle calculations, octahedral

Abstract

Isostrutural II-VI alloys whose components are either rocksalt stable (e.g., CaO-MgO) or zincblende stable (e.g., ZnS-ZnSe) are known to be thermodynamically unstable at low temperatures, showing a miscibility gap and no bulk ordering. In contrast, we show that heterostructural MgO-ZnO is stable, under certain conditions, in the sixfold-coordinated structure for Zn concentrations below 67%, giving rise to spontaneously ordered alloys. Using first-principles calculations, we explain the origin of this stability, the structures of their low-temperature ordered phases, short-range-order patterns, and their optical band-gap properties.

Original Publication Citation

M. Sanati, G. L. W. Hart, and A. Zunger, "Ordering Tendencies in Octahedral MgO-ZnO Alloys," Phys. Rev. B 68 15521 (24 Oct. 23). The original article may be found here: http://prb.aps.org/abstract/PRB/v68/i15/e15521