Cationic and anionic concentration dependent elastic properties of zinc blende specimens within CdxZn1-xSySe1-y quaternary system: Calculations with density functional theory

Elastic properties of zinc blende CdxZn1-xSySe1-y quaternary alloys have been calculated with density functional theory oriented FP-LAPW scheme. Elastic stiffness constants and hardness of specimens have been increased almost linearly with increasing sulphur composition at each fixed cadmium composition, while their decrease have been observed with increasing cadmium composition at each fixed sulphur composition in any binaryternary/ternary-quaternary system. Mechanical and dynamical stability, elastic anisotropy, compressibility, ductility and fair plasticity have been calculated as the key features of each specimen. Mixture of covalent and ionic bonding with dominant role of covalent, central nature of interatomic forces and bending over stretching in chemical bonds have been observed in each compound. Calculated Debye temperature suggests ZnS as the stiffest and CdSe as the softest among all compounds. Calculated Gruneisen parameter has confirmed anharmonic nature of interaction between the atoms. Thermal conductivities and melting temperatures of all the specimens have also been computed.