Structural and Magnetic Properties of the Ternary Manganese Compound Semiconductors MnAl2Te4, MnIn2Te4, and MnIn2Se4

Abstract

The tetragonal compounds MnAl2Te4 and MnIn2Te4 and the layered MnIn2Se4, with rhombohedral symmetry, are synthesized by melting a stoichiometric mixture of the elements or by chemical vapour transport technique. The temperature dependence of the lattice parameters shows a linear expansion with no structural transition. The magnetic susceptibility follows a Curie-Weiss behaviour but at low temperatures (< 70 K) deviations appear. The magnetic properties are discussed in terms of magnetic frustration in presence of chemical disorder of Mn and In or Al sites, preventing long-range order.