First-Principle Calculations of the Structural, Electronic, and Thermal Properties of Cr2NbSn1-xPbx Quaternary Heusler Alloys

The electronic structure, elastic, and magnetic properties of the Cr2NbSn1 - xPbx quaternary Heusler alloys have been investigated using the full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory and implemented in WIEN2k code. The exchange-correlation potential is evaluated using the generalized gradient approximation (GGA) within the Perdew-Burke-Ernzerhof (PBE) parameterization. Our results provide a theoretical study for the mixed Cr2NbSn1 - xPbx Heusler alloys in which no theoretical or experimental data are currently available. The AlCu(2)Mnl-type (L2(1)) structure is more stable than the CuHg2Ti-type structure at equilibrium volume for the compounds. In their equilibrium L2(1) structure, all concentrations are magnetic and metallic. However, there is linear variation of the lattice parameter. The bulk modulus, the elastic constants, and the Debye temperature were studied with a variation of composition x of Pb. The mechanical results show that these compounds are mechanically stable. The quasi-harmonic Debye model, as implemented in the Gibbs code, was used to predict the thermal properties of the Cr2NbSn1 - xPbx alloys. These alloys seem to be a potential candidate of spintronic devices.