An ab initio study of structural, elastic and electronic properties of hexagonal MAuGe (M = Lu, Sc) compounds

TL;DR

This study uses first-principles calculations to analyze the structural, elastic, and electronic properties of hexagonal LuAuGe and ScAuGe compounds, confirming their stability and detailing their mechanical and electronic characteristics.

Contribution

It provides a comprehensive theoretical analysis of LuAuGe and ScAuGe compounds, including structural, elastic, and electronic properties, validated against experimental data.

Findings

Structural parameters agree with experimental data.

Elastic constants satisfy stability criteria.

Electronic band structures and densities of states are characterized.

Abstract

In this paper, we performed a detailed theoretical study of structural, elastic and electronic properties of two germanides LuAuGe and ScAuGe by means of first-principles calculations using the pseudopotential plane-wave method within the generalized gradient approximation. The crystal lattice parameters and the internal coordinates are in good agreement with the existing experimental and theoretical reports, which proves the reliability of the applied theoretical method. The hydrostatic pressure effect on the structural parameters is shown. The monocrystalline elastic constants were calculated using the stress-strain technique. The calculated elastic constants of the MAuGe (M = Lu, Sc) compounds meet the mechanical stability criteria for hexagonal crystals and these constants were used to analyze the elastic anisotropy of the MAuGe compounds through three different indices. Polycrystalline isotropic elastic moduli, namely bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and the related properties are also estimated using Voigt-Reuss-Hill approximations. Finally, we studied the electronic properties of the considered compounds by calculating their band structures, their densities of states and their electron density distributions.