Investigation on the structural,elastic, electronic,and magnetic properties of half-metallic $$hbox {Co}_{2}hbox {MnSi}$$ and CoMnIrSi via first-principles calculations

We investigated the structural, elastic, electronic, and magnetic properties of (hbox {Co}_{2}hbox {MnSi}) and CoMnIrSi full-Heusler compounds by means of density functional theory based on the full-potential linearized augmented plane wave (FP-LAPW) approach. The generalized gradient approximation as proposed by Wu and Cohen (GGA-WC) was employed to treat the exchange-correlation effect. The results show that both alloys are structurally and mechanically stable. (hbox {Co}_{2}hbox {MnSi}) is almost elastically isotropic, while CoMnIrSi is anisotropic, and both alloys are ductile. The studied compounds have perfect spin polarization of 100 %, with down-spin bandgap of 0.796 eV and 0.728 eV, respectively. The calculated magnetic properties indicate that the Slater–Pauling rule is satisfied in both cases. Finally, the effect of strain on the half-metallic properties of (hbox {Co}_{2}hbox {MnSi}) and CoMnIrSi was also investigated by varying the lattice constant over a wide range.