The complex structure of Fe2+(3d6) magnetism in HgSe1−ySy mixed crystals

Abstract

High magnetic field magnetization measurements of Hg~ _ x Fex Sex _ y Sy (x = 0.002, y = 0.17; y = 0.28) at temperatures ranging from 1.6 to 119 K and in magnetic fields up to 20 T are reported. The magnetization of the Fe 2 + (3d 6) ion in the investigated mixed anion crystals is shown to be different from the Van Vleck behaviour. A theoretical description of the experimental data is based on an assumption that the electronic structure (and thus magnetic properties) of the Fe2+(3d 6) ion in a mixed anion crystal depends on its local environment. In this model the total magnetization is calculated as a statistically weighted sum of magnetizations found for specific local configurations. The model provides a good quantitative description of the experimental data.