DFT based comparative study of the physical properties of MAlB (M = V, Ta, Mo, Nb) MAB compounds

MAB phases have appealing physical features that make them appropriate for a wide range of applications. Motivated by this, we present density functional theory (DFT) calculations of the structural, elastic, bonding, electronic band dispersion, acoustic behavior, phonon spectrum, various thermomechanical and optoelectronic properties of VAlB and TaAlB ternary borides for the first time. The computed ground state lattice parameters of both compounds are very consistent with experimental data. The formation enthalpy, elastic constants, and phonon dispersion calculations indicate that both compounds are chemically, mechanically, and dynamically stable, respectively. The physical parameters of VAlB and TaAlB are studied and compared with those of MoAlB and NbAlB MAB compounds.