Mossbauer study of Zn0.4Cu0.6Fe1.2Cr0.8O4

Zn0.4Cu0.6Fe1.2Cr0.8O4 has been studied by Mossbauer spectroscopy, SQUID magnetometry, and X-ray diffraction. The crystal is found to have a cubic spinel structure with the lattice constant a(0) = 8.3667 Angstrom. The iron ions are in ferric states and occupy both the tetrahedral (A) and octahedral (B) sites; the fractions of the iron ions at the A-sites and B-sites are 0.52 and 0.34, respectively. While spin orderings are collinear at higher temperatures, spin canting begins to appear around 25 K and increases with decreasing temperature; the canting angle at 4.7 K reaches up to 27degrees. Debye temperatures of the tetrahedral and octahedral sites are determined to be 339 and 335 K, respectively. (C) 2003 Elsevier Ltd. All rights reserved.