Study of elastic, thermodynamic and dielectric properties of CdAs ₂ : a DFT approach

Abstract The elastic, thermodynamic and dielectric properties of CdAs 2 have been investigated using VASP software. The pressure dependent elastic stiffness coefficients of CdAs 2 have been computed. This investigation explores the directional Young’s modulus and linear compressibility of the crystal through polar plots. The minimum and maximum values of Young’s modulus, shear modulus and linear compressibility are obtained using ELATE software. The computed Debye temperature of CdAs 2 is 246.8 K. Our study reveals the variations of specific heat, entropy and coefficient of thermal expansion of CdAs 2 with temperature. The average coefficient of linear thermal expansion is approximately <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>25</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>6</mml:mn> </mml:mrow> </mml:msup> <mml:mspace width="0.25em"/> <mml:msup> <mml:mrow> <mml:mi mathvariant="normal">K</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> in temperature range of 300–600 K. The energy dependence of the principal dielectric constants, principal refractive indices and reflectivity is explored in the energy range of 0–20 eV. The present investigation shows that CdAs 2 has definite elastic and dielectric anisotropies.