Article ID Journal Published Year Pages File Type
1606563 Journal of Alloys and Compounds 2016 7 Pages PDF
Abstract

•Vickers hardness suggests that WZ-CdSe0.5Te0.5 as the hardness for all changes of x.•The ZB and WZ of CdSexTe1−x alloys are mechanically stable for all Te concentrations.•CdSe is mechanically found to be the strongest material in the CdSexTe1−x alloys.•Young's modulus indicates that ZB- CdSe0.5Te0.5 is the stiffest for all changes of x.•The ionic bonds are found to be more dominant for all changes of x.

First-principles calculations are carried out to perform the structural properties using two dimensional search of equation of state (EOS), elastic constants and thermodynamic properties for zinc-blende (ZB) and wurtzite (WZ) phases of CdSexTe1−x alloys for all compositions x (x = 0, 0.25, 0.5, 0.75, 1). We have used the full-potential linearized augmented plane wave (FP-LAPW) method within the density functional theory (DFT), which has been implanted in the WIEN2k code, along with the improved generalized gradient approximation (PBE-GGA) to treat exchange-correlation functional. The mechanical and thermodynamic properties of CdSexTe1−x alloys are studied using the optimized lattice parameters from two dimensional search of EOS at zero pressure. The ZB and WZ phases of the ternary CdSexTe1−x alloys are found to be mechanically stable within PBE-GGA exchange-correlation over all the range of the Te concentrations (x = 0, 0.25, 0.5, 0.75, 1). We have found that the CdSe is mechanically the strongest material in the ternary CdSexTe1−x alloys. We concluded that the calculated values of Cauchy pressure and Poisson's ratio predict that the ionic bonds for both ZB and WZ phases of CdSexTe1−x ternary alloys are more dominant for all compositions of x(x = 0, 0.25, 0.5, 0.75, 1) within PBE-GGA exchange-correlation. Our results exhibit a non-linear relationship between elastic constants and Se concentrations. Moreover, the elastic properties of cubic (ZB) and hexagonal (WZ) phases of CdSexTe1−x alloys, including elastic constants, bulk and shear moduli are calculated and compared with available theoretical and experimental results, good agreement was found.

Related Topics
Physical Sciences and Engineering Materials Science Metals and Alloys
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