Investigation of new d0 half-metallic full-heusler alloys N2BaX (X=Rb, Cs, Ca and Sr) using first-principle calculations

Abstract

The first-principle density functional theory (DFT) calculations were employed to investigate the structural, elastic, electronic, magnetic properties and half-metallicity of N2BaX (X = Rb, Cs, Ca and Sr) new d0 half-metallic full-Heusler compounds with Hg2CuTi-type and Cu2MnAl-type structures within generalized gradient approximation Perdew, Burke, and Ernzerhof GGA-PBE and the modified Becke-Johnson potential mBJ-GGA-PBE for the exchange correlation potential. Total energy calculations show that formation of these alloys in Cu2MnAl-type structure are energetically favorable and are more stable in the ferromagnetic phase than Hg2CuTi-type structure. We have found that N2BaX (X = Rb, Cs, Ca and Sr) alloys in Cu2MnAl-type structure are half-metallic ferromagnets with an integer total magnetic moment at the equilibrium lattice constant, which were in agreement with Slater–Pauling rule (Mtot = 16-Ztot). The half-metallicity was discussed for N2BaX using the energy band structure, our calculations show that the minority spin channel has metallic nature and the majority spin channel has a wide semiconducting gap of 3.78, 4.60, 5.44 and 3.74eV and they has a huge half-metallic gap of 1.56, 2.33, 2.39 and 1.59 eV for N2BaCa, N2BaCs, N2BaRb and N2BaSr respectively with the mBJ-GGA-PBE.