Pressure dependent mechanical and thermodynamical properties of Hg 0.91 Mn 0.09 Te semiconductor

The mechanical, thermodynamical and elastic properties of Hg 0.91 Mn 0.09 Te compound are calculated by formulating an effective interionic interaction potential. This potential consists of the long-range Coulomb, three body force parameter, the Hafemeister and Flygare type short-range overlap repulsion extended upto the second neighbor ions and the van der Waals (vdW) interaction. The estimated values of phase transition pressure have revealed reasonably good agreement with the available experimental data on the phase transition pressure P t =11.5 GPa and the vast volume discontinuity in pressure-volume (PV) phase diagram indicate the structural phase transition from zincblende (B3) to rock salt (B1) structure. Later on, the Poisson’s ratio ν, the ratio R S/B of S (Voigt averaged shear modulus) over B (bulk modulus), elastic anisotropy parameter, elastic wave velocity, average wave velocity and Debye temperature as functions of pressure is calculated. From Poisson’s ratio and the ratio R S/B it is inferred that Hg 0.91 Mn 0.09 Te is brittle in nature in both B3 phase and B1 phase. To our knowledge this is the first quantitative theoretical prediction of the pressure dependence of ductile (brittle) nature of Hg 0.91 Mn 0.09 Te compounds and still awaits experimental confirmations. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2011