The ground-state properties of a new full-Heusler alloy Pd2MnPb: DFT+U, QTAIM, and MFA investigations

Abstract

First principles methods have largely contributed in the prediction of new compounds by demonstrating many of their physical properties. This work is based on the same background in which it presents a first prediction of structural properties, the determination of the most stable magnetic ordering, the prediction of energy and mechanical stabilities and the analysis of electronic and magnetic properties of a new Pd2MnPb alloy in the full-Heusler structure. The study of structural properties has allowed the prediction of the lattice parameter, bulk modulus and its pressure derivative of Pd2MnPb in three magnetic orders (non-magnetic, ferromagnetic, and antiferromagnetic). The obtained results for ferromagnetic and antiferromagnetic orders are similar while they are different from those obtained for the non-magnetic one. The comparison between the minima of E = F(V) curves of the three magnetic orders has shown that Pd2MnPb is a ferromagnetic compound. The mechanical stability of this compound has been verified and the results of the elastic constants have shown that this compound has a large elastic anisotropy. The electronic properties have shown that it has a metallic behavior. The Curie temperature has been predicted using mean-field approximation after a calculation of the exchange coupling parameters Jij by spin polarized relativistic Korringa–Kohn–Rostoker method. The obtained results have confirmed the ferromagnetic behavior of this compound. The analysis of bonding natures between the different atoms that form Pd2MnPb has shown that all of them have a strong covalent character.