Résumé:
We report on structural and magnetic properties of the spinel compound CuCrZrSe4. Rietveld refinement of the powder x-ray diffraction patterns reveals the normal spinel structure AB2Se4,
wherethe Zr4+ and Cr3+ ions occupy the B sites, while the Cu1+ ions are located on A sites. The magneticsusceptibility reveals a Curie–Weiss law above 250 K with a ferromagnetic Curie–Weiss temperatureθp = 115 K and an effective paramagnetic moment meff𝝁eff 3:75𝝁B per Cr3+ ion corresponding to a g valueg =1.94 in fair agreement with electron spin resonance (ESR) measurements. Below 100 K themagnetization deviates from the Curie–Weiss behaviour and splits into field-cooled (FC) and zerofield-cooled (ZFC) branches. A second anomaly in the magnetization close to 10 K, which is also visiblein the ESR parameters, indicates the transition into a spin-glass state due to the random distribution ofZr and Cr ions on the B site. This is supported by the frequency dependence of the anomaly detected byAC susceptibility measurements