Structure and Ferromagnetism in Mn⁴⁺ Spinels: AM_0.5Mn_1.5O₄ (A = Li, Cu; M = Ni, Mg)

Abstract

The structure and electronic properties of a series of MnIV spinel oxides, with the general formula, AM0.5Mn1.5O4 (A = Li, Cu; M = Ni, Mg), are investigated. These materials form an interesting analogy to pyrochlore structures that show colossal magnetoresistance properties. Studies of all the compounds show spontaneous magnetization at a well-defined transition temperature and their semiconducting nature.