Magnetic and structural properties of the chromium-based Mn1−xCdxCr2S4 thiospinel

The (Mn_1−xCd_x)Cr₂S₄ phases (0 ≤ x ≤ 0.6) have been synthesized from the corresponding elements at 1123 K. These samples were characterized by powder X-ray diffraction (XRD) and magnetic susceptibility. The (Mn_1−xCd_x)Cr₂S₄ compounds crystallize in the space group Fd-3m with cell parameters a = 10.101(6) Å, 10.139(3) Å, 10.165(2) Å, and 10.192(1) Å for x = 0, 0.2, 0.4 and 0.6, respectively. An overall ferrimagnetic behavior is observed for all samples. The ferromagnetic component increases rapidly when manganese is substituted by non-magnetic cadmium, as shown by ZFC/FC measurements. At the same time, the value of the magnetization M₅₀ at 50 kOe, deduced from M(H) loops, also increases with increasing cadmium content because the antiferromagnetic alignment between chromium and manganese spins is progressively lost, leading toward well aligned moments pointing into the same direction. These results are explained by a rearrangement of the chromium spins when Mn located at the tetrahedral sites, is substituted by Cd.