Structural, magnetic, electronic and elastic properties of half-metallic ferromagnetism full-Heusler alloys: Normal-Co2TiSn and inverse- Zr2RhGa using FP-LAPW method

The equilibrium structural parameters, electronic, magnetic and elastic properties of the inverse Zr2RhGa and normal Co2TiSn Full-Heusler compounds have been studied using density-functional theory (DFT) and full-potential linearized augmented plane-wave (FP-LAPW) method as implemented in the WIEN2k package. The Generalized Gradient Approximation (GGA) has been used for the exchange-correlation potential (V-xc) to compute the equilibrium structural parameters; lattice constant (a), bulk modulus (B) and bulk modulus pressure derivative (B'). In addition to the GGA approach, the modified Becke Johnson (mBJ) scheme has been used to calculate the band gap energies. The normal Heusler Co2TiSn compound and the inverse Heusler Zr2RhGa compound within GGA and mBJ approaches are found to have a half-metallic behavior, with an indirect energy gap in the spin down configuration. The calculated total magnetic moments for both compounds are to some extent compatible with the available experimental and theoretical results. Elastic constants and their related properties were obtained by using the IRelast package. These compounds are mechanically stable. The elastic constants satisfy the Born mechanical stability criteria. B/S ratio shows that the normal Co2TiSn has a brittle nature, while the inverse Zr2RhGa has a ductile nature; Poisson's ratio (nu) values show that both compounds have an ionic bond nature.