Theoretical investigation of magnesium and selenium concentration dependent elastic properties of zinc blende specimens under the MgxZn1-xSeyTe1-y quaternary system with density functional FP-LAPW approach

Abstract

First principle calculations are carried out to investigate elastic stiffness constants and allied mechanical properties of the zinc blende specimens under the MgxZn1-xSeyTe1-y quaternary system. Magnesium and selenium concentration dependence of these properties is also investigated. Computed elastic stiffness constants show the trend C11>C12>C44 in each specimen. Elastic stiffness constants and hardness of specimens increase nonlinearly with increasing selenium composition at each fixed magnesium composition, while they decrease with increasing selenium-composition at each fixed magnesium-composition in any binary-ternary or ternary-quaternary system. Each specimen exhibits mechanical stability, elastic anisotropy, compressibility, ductility and plasticity. Mixed bonding with dominancy of covalent character over ionic, dominancy of bending over stretching in chemical bonds and central character of inter-atomic force are observed in each specimen. The anharmonic nature of interaction between the atoms in each specimen is confirmed from the calculated Grüneisen parameter. The calculated thermal conductivity and melting temperature of each specimen are also reported in the present article.