Theoretical investigation of structural, elastic, and electronic properties of ternary boride MoAlB

Using first-principles calculations, the structural, elastic, and electronic properties of MoAlB have been investigated. The optimized lattice constants exhibit fair agreement with the experimental results. The computed elastic constants satisfy the mechanical stability conditions for MoAlB. The Mo-based boride MoAlB is elastically anisotropic and classified as brittle material. This boride is expected to be thermally conductive due to its high Debye temperature of 693K. The metallic conductivity of this compound is predicted by means of electronic structure calculations. The chemical bonding in MoAlB is basically covalent that is assured with the results of DOS, Mulliken population, and charge density distribution. The hardness value of 11.6GPa for MoAlB suggests that it is relatively soft compared to many others borides. The Fermi surface is formed due to low dispersive Mo 4d-like bands, which makes the compound a conductive one.