Recently synthesized (Ti1-xMox)2AlC (0 < x < 0.20) solids solutions: Deciphering the structural, electronic, mechanical and thermodynamic properties via ab initio simulations

TL;DR

This study uses ab initio simulations to analyze how Mo substitution affects the structural, electronic, mechanical, and thermodynamic properties of (Ti1-xMox)2AlC solids, revealing enhanced covalent bonding, brittleness, and anisotropy.

Contribution

It provides a comprehensive first-principles analysis of (Ti1-xMox)2AlC, highlighting the effects of Mo substitution on various physical properties for the first time.

Findings

Lattice constants match experimental data.

Electronic structure confirms metallic nature.

Mo substitution strengthens covalent bonds and enhances mechanical properties.

Abstract

The structural, electronic, mechanical and thermodynamic properties of (Ti1-xMox)2AlC (0 < x < 0.20) were explored via density functional theory. The obtained lattice constants agree well with the experimental values. The electronic band structure confirms the metallic nature. Strengthening of covalent bonds due to Mo substitution is confirmed from the study of band structure, electronic density of states and charge density mapping. The elastic constants satisfy the mechanical stability criteria. Strengthening of covalent bonds leads to enhanced mechanical properties. (Ti1-xMox)2AlC compounds are found to exhibit brittle behavior. The anisotropic nature of (Ti1-xMox)2AlC is revealed from the direction dependent Young's modulus, compressibility, shear modulus and Poisson's ratio as well as the shear anisotropic constants and the universal anisotropic factor. The Debye temperature, minimum thermal conductivity, Gruneisen parameter and melting temperature of (Ti1-xMox)2AlC have been calculated for different Mo contents. Our calculated values are compared with reported values, where available.