Synthesis and Magnetic Properties of Silver-Doped Iron Dichromium Tetrasulfide

We have synthesized Fe1 – xAgxCr2S4 (0 < x < 0.5) solid solutions via doping of the FeCr2S4 thiochromite with silver. From a break in the composition dependence of the unit-cell parameter for the synthesized materials, the solid solution series has been shown to be limited by x = 0.22. The magnetic properties of the solid solutions have been studied at temperatures from 4 to 300 K in a magnetic field H = 3980 A/m (50 Oe). All of the materials have been shown to be ferrimagnets with a Curie temperature rising with silver concentration: from 185 K at x = 0 to 203 K at x = 0.22. We have determined saturation magnetic moments of the solid solutions and proposed a model that accounts for their observed magnetic properties.