Study of the spin-glass transition in FeCr2xIn2-2xS4 thiospinel

The spin-glass (SG) transition in Fe(In2-2xCr2x)S-4 thiospinel with x = 0.1 and 0.3 has been studied by susceptibility and Mossbauer measurements. It is found that iron in the system is partially inverted, with similar to 80% high-spin Fe2+ iron at octahedral sites. AC susceptibility data show a spi n-glass-like transition at T-SG = 10 K that depends on the driving frequenc y f, following a Vogel-Fulcher law. Below T-SG, the splitting of Zeeman lev els yields a complex Mossbauer spectrum, which was fitted using a full Fe-5 7-nuclear Hamiltonian with quadrupolar and magnetic interactions. The reduc ed magnetic hyperfine field b(T) = B(T)/B-s is well described by a Langevin function L(x), with Te = 12.8(3)K and B-s = 16.8(3)T, (C) 2001 Elsevier Sc ience B.V. All rights reserved.