Modeling of Elastic and Mechanical Properties of ZnS Using Mehl Method

Abstract

The elastic constants of the materials are essential to understand the matter behaviors. The accurate measurement of elastic constants is based on non-destructive and destructive methods. Theoretically, Density Functional Theory DFT is an accurate tool for the determination of physical properties of crystals. The main purpose of this paper is to show the reliability and the accuracy of elastic behaviors characterization within theoretical method as regards to it seniority. We have performed self-consistent calculations to investigate the elastic and mechanical properties of ZnS. The numerical processing model of the application of orthorhombic and monoclinic constraints via Mehl method which enable the identification of all the elastic stiffness coefficients (C11, C12 and C44) of an cubic material, is described. The reliability and accuracy of the identification are discussed. In addition, other mechanical properties including: bulk modulus (B), Kleinman parameter (ζ), Shear (G) and Young (E) moduli, Poisson’s ratio (υ), Lame’s coefficients (λ and μ), Debye temperature (ϴD) and anisotropy factor (A) are calculated for both structures of ZnS Zinc-blende (B3) and Rocksalt (B1). The elastic and mechanical properties of ZnS at ambient conditions and under high pressure are successfully obtained. The trends in physical properties are also discussed and compared with the available results. Our results are in reasonable agreement with the available theoretical and experimental works.