Magnetic Properties of Zn_1−xNi_xCr₂S₄(0≤x≤0.40) with Spinel Structure

Abstract

Magnetization and susceptibility measurements were made on polycrystalline samples of Zn_1−xNi_xCr₂S₄ from 4.2 K to 800 K in magnetic fields up to 16.5 kOe. The inverse susceptibilities except for ZnCr₂S₄ show a non-linear behavior characteristic of a ferrimagnet. This indicates that the system has a magnetic moment on Ni²⁺ in contrast with NiRh₂S₄ and the sign of Ni²⁺–Cr³⁺ exchange interaction is negative. The saturation magnetization of the sample (x=0.40) is equal to 3.0±0.1 μ_B/molecule at 4.2 K. Electrical resistivity of the sample (x=0.40) was measured between 77 K and 300 K, and it is semiconducting (3×10³Ω cm at R. T.).