Ab initio study of the structural, phonon, elastic and thermodynamic properties of the ordered Ge0.5Sn0.5 cubic alloy under high pressure

A theoretical investigation on the structural, phonon, elastic and thermodynamic properties of the ordered Ge0.5Sn0.5 cubic alloy has been conducted using the norm-conserving psudopotentials within the local density approximation in the frame of the density functional theory (DFT) and the density functional perturbation theory (DFPT) in the ABINIT code. We present that the ordered Ge0.5Sn0.5 cubic alloy in the zinc-blende phase keeps dynamically stable until 9 GPa. The elastic constants and thermodynamic quantities as a function of pressure and temperature are also reported. (C) 2012 Elsevier B.V. All rights reserved.