HEUSLER COMPOUNDS WITH MN - A MODEL FOR SOME MAGNETIC-PROPERTIES

A two sublattice model is proposed to describe the magnetic behaviour of pseudo-ternary Heusler compounds (X(1-x)X'(c))(2)YZ. We assume in t he applications reported here that impurities are selectively introduc ed in the sublattice of atoms X. The disorder is treated within the co herent potential approximation. The exchange interaction between local ized Mn magnetic moments is calculated for several neighbours of a giv en Mn atom, and for a given set of model parameters. Using these resul ts the Curie temperature is estimated as a function of concentration.