Half-Metallic Properties of the Ru2ZrSb Full-Heusler Compound: a First-Principles Study

A first-principles study on the electronic structure and magnetic properties of the Ru2ZrSb Heusler compound has been performed by using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method. It is found that the AlCu2Mn-type structure exhibits half-metallic ferrimagnetism and is preferable energywise than the CuHg2Ti-type structure. The total spin magnetic moment is based on mainly the Ru atoms and obeys the Slater-Pauling rule. The calculated total magnetic moment of Ru2ZrSb is -1.0 mu (B) at the equilibrium lattice constant 6.497 for the AlCu2Mn-type structure. The spin-down electrons are metallic, but the spin-up bands are semiconductor with a gap of 0.388 eV, and the spin-flip gap is 0.313 eV. The AlCu2Mn-type Ru2ZrSb Heusler compound keeps a 100 % of spin polarization for lattice constants ranging between 6.40 and 6.53 . The Curie temperature is estimated to be 322.7 K in the mean field approximation (MFA).