First-Principles Investigation of Structural and Electronic Properties and Spin Polarizability of Cu(3–x)MnxAl (x = 0, 1) Intermetallic Compounds

Intermetallic compounds (IMCs) including transition metals and p-block metals exhibit high resistance to corrosion and oxidation, low density, high conductivity, and magnetic polarizability. In this study, the first-principles calculations method based on Density Functional Theory (DFT) has been used to investigate the structural and electronic properties, charge density distribution, spin polarizability, and magnetic behavior of Cu(3–x)MnxAl (x = 0, 1) intermetallic compounds. Generalized Gradient Approximation (GGA) was employed with Perdew-Burke-Ernzerhof (PBE) exchange-correlation. Calculation of metallic and conductive nature and structural properties was performed simultaneously for all crystal lattices of Cu(3–x)MnxAl (L12, D03, and Heusler L21) with 221-Pm3m, 225-Fm3m space groups. Notably, the study clarifies the stoichiometric similarity and difference between L12 and D03 type structures by presenting a detailed discussion of the D03 structure and its targeted properties for the first time. The lattice constant values obtained by performing various optimizations are in excellent agreement with previously reported experimental and theoretical data. The electron density distribution and population analysis are consistent and reveal the dominant bonding type in each IMC. Furthermore, Spin Polarizability analysis has been carried out to demonstrate the magnetic nature of the Cu2MnAl (L21) Full Heusler alloy upon the addition of the Mn atom.