SPIN-GLASS LIKE BEHAVIOR IN A CONCENTRATED CHROMIUM SPINEL - ZN0.5CD0.5CR2S4

Low field d.c. and a.c. susceptibility measurements are reported for the non magnetically diluted spinel Zno.sCdo.sCr2S4. A spin-glass like behaviour is observed at low temperature (TF = 15.4 K at g = 198 Hz). This is the result of the presence of competing interactions (ferromagnetic between nearest-neighbours and antiferromagnetic between higher order neighbours) and of the disorder of their distribution due to the substitution between non-magnetic zinc and cadmium ions in the tetrahedral sites of the spinel lattice.