Ab initio structural parameters and transition pressures of GaN_xAs_1−x dilute alloys

Abstract

The results are presented of an ab initio total energy study of the high-pressure phases of GaN _x As_{1− x} dilute alloys calculated within the full-potential linearized augmented plane wave method in the generalized gradient approximation. Three candidate structures, namely zinc-blende, rocksalt and CsCl, have been considered. In each case, the structural parameters and transition pressures of dilute alloys of interest are calculated. In agreement with earlier calculations of Stenuit and Fahy [Phys. Rev. B 76 (2007) 035201], the deviation of the lattice constants from Vegard's law for zinc-blende GaN _x As_{1− x} alloys is found to be negligible.

Keywords:

• structural properties
• transition pressure
• dilute alloy
• high pressure