Effect of swap disorder on the physical properties of the quaternary Heusler alloy PdMnTiAl: a first-principles study

Heusler alloys crystallize in a close-packed cubic structure, having a four-atom basis forming a face-centred cubic lattice. By selecting different composite elements, Heusler alloys provide a large family of members for frontier research of spintronics and magnetic materials and devices. In this paper, the structural, electronic and magnetic properties of a novel quaternary Heusler alloy, PdMnTiAl, have been investigated using a first-principles computational materials calculation. It was found that the stable ordered structure is a non-magnetic Y-type1, in good agreement with the Slater-Pauling rule. From the band structure and the density of states, it is predicted that this Y-type1 configuration is a new gapless semi-metal material. Furthermore, it was discovered that the Pd-Mn swap-disordered structure is more stable than the Y-type1 structure. The present work provides a guide for experiments to synthesize and characterize this Heusler alloy.