Ab-initio study of mechanical and electronic properties of MoAlB

TL;DR

This study uses first-principles calculations to explore the structural, elastic, electronic, and bonding properties of MoAlB, revealing its mechanical stability, anisotropy, conductivity, and covalent bonding nature.

Contribution

It provides the first detailed ab-initio analysis of MoAlB's properties, including elastic constants, electronic structure, and bonding characteristics.

Findings

MoAlB is mechanically stable and elastically anisotropic.

It exhibits metallic conductivity and covalent bonding.

The estimated hardness is 11.6 GPa, indicating softness compared to other borides.

Abstract

Using first-principles calculations, the structural, elastic and electronic properties of MoAlB have been investigated for the first time. The optimized lattice constants exhibit fair agreement with the experimental values. The computed elastic constants satisfy the mechanical stability conditions for the MoAlB. The Mo-based boride MoAlB is elastically anisotropic and can be classified as brittle material. This boride is expected to show reasonable thermal conductivity due to its high Debye temperature of 693 K. The metallic electrical conductivity of this compound is predicted from the electronic band structure calculations. The chemical bonding in MoAlB is basically covalent in nature which is supported by the calculated electronic density of states (DOS), Mulliken population, and charge density distribution. The estimated hardness value of 11.6 GPa for MoAlB suggests that it is softer compared to many other borides. The Fermi surface is formed due to low dispersive Mo 4d-like bands, which makes the compound a conductive one.