Magnetic Phase Diagram of CuCr2–xSbxS4 Solid Solutions

Resumo

The magnetization of CuCr_2–xSb_xS₄ solid solutions has been measured as a function of temperature between 300 and 5 K in a weak (3980 A/m) and a strong (7960 A/m) magnetic field. We have identified the type and character of the magnetic transformations observed in the system and determined the temperature and composition limits of the stability regions of the magnetically active phases involved and the cation and valence distributions in them. A magnetic phase diagram of the synthesized materials has been mapped out, where the largest area (0 < x < 0.23) after the paramagnetic region is occupied by solid solutions based on the CuCr₂S₄ ferromagnet. In the composition range (0.23 < x < 0.40) adjacent to the infinite clusters—CuCr₂S₄ ferromagnet and CuCr_1.5Sb_0.5S₄ antiferromagnet—the phase diagram contains medium and small finite ferro- and antiferromagnetic clusters forming a short-range magnetic order or spin glass. The compositions based on the CuCr_1.5Sb_0.5S₄ antiferromagnet lie in the composition range 0.4 < x < 0.5.