The Magnetic Susceptibility of Iron Ditelluride: II

The magnetic susceptibility of stoichiometric iron ditelluride has been measured between 15° and 100°K. The material appears to be antiferromagnetic with a Néel temperature at about 85°K. The curve is anomalous in that the susceptibility at 15°K is greater than that at the Néel temperature. This behaviour can be explained by a simple model of an antiferromagnetic containing some non-magnetic ions, provided that the concentration of the latter changes as a result of the ordering process.