The Magnetic Properties and Phase Diagram of Iron Tellurium System

Abstract

In the present paper, studies on the phase diagram and magnetic properties of Fe–Te system are reported. It was found by X-ray and thermal analysis that a number of intermetallic compounds are formed from melt through peritectic reactions, and an eutectoid reaction was seen to occur between two compounds α (ca FeTe) and β (ca FeTe₂) at 520°C, the reactions product having NiAs structure. The α phase shows an antiferromagnetic behavior with asymptotic Curie temperature θ=130°K, Curie-Weiss constant C=0.57, but the crystal lattice type of this compound is obscure at present. The β phase has a crystal lattice of the markasite type and is antiferromagnetic, with θ=67°K and C=1.31. The γ phase which has a crystal lattice of the NiAs type shows an antiferromagnetic behavior, with θ=800°K and C=1.15. A short discussion on the antiferromagnetism of these compounds is given.