Investigation of structural, mechanical, dynamic stability and electronic properties of anti-perovskite nitrides ANLa3 (A = Al, Ga): a DFT and DFPT studies

Abstract

Various properties of anti-perovskites ANLa3 (A = Al, Ga) are investigated using the density functional theory (DFT). The GaNLa3 properties are studied for the first time. The computed lattice parameter of AlNLa3 is found to be close to other theoretical and experimental results. The mechanical stability of the present compounds are confirmed by the elastic constants estimated through the calculations. Furthermore, bulk modulus, shear modulus and Young’s modulus are evaluated. In this report, the dynamic stability and formation energy of AlNLa3 and GaNLa3 alloys are also highlighted. The state density functional perturbation theory (DFPT) is used to reveal the phonon calculation showing that the studied compounds are dynamically stable. Indeed, with a negative formation energy, it has been predicted that the GaNLa3 compound can be synthesized experimentally. Moreover, the electronic properties are studied using the Perdew–Burke–Ernzerhof Generalized Gradient Approximation (GGA-PBE) as well as a more sophisticated exchange-correlation Yukawa Screened PBE0 (YS-PBE0) hybrid functional.It has been found that the computed energy band structures within both approaches, that the anti-perovskites AlNLa3 and GaNLa3 are metallic nature. The total density of states (TDOS) and partial density of states (PDOS) are also calculated to show in evidence the contribution of atoms orbitals in the formation of bands.