LAUSR

Abstract The magnetic properties tuning and volume dependence in the series of quaternary full Heusler alloys with formula Co 2 Cr 1 − x Y x Ga ( Y = Ti , V, Mn, Fe, Co, Ni) were studied with a detailed first-principles exploration. We employ the density functional KKR method with the coherent potential approximation, estimating effective Heisenberg exchange constants via the magnetic force theorem together with mean-field Curie temperature ( T C ) and magnetic moment for compositions in the whole concentration range. The volumetric dependency of these magnetic properties is studied, particularly the pressure derivatives of T C at equilibrium. Our ternary alloy calculations show good agreement with local-density and generalized gradient approximations in the literature. The quaternary alloys show a wide range of tunable magnetic properties, where magnetic moments range from 0.8 to 4.9  μ B , T C from 130 K to 1250 K, and dT C / dV values range from −7 to + 6.3 K A − 3 .