Mِssbauer studies on Zn-substituted iron molybdate

Mössbauer spectra of Fe2−yZnyMoO4 spinel ferrites were recorded in their paramagnetic state. Paramagnetic Mössbauer spectra of all the samples show broad absorption peaks due to the presence of Fe2+ and Fe3+ ions on both sites (A and B) of the spinel lattice. All the spectra have been fitted with four doublets, using a least squares fitting program. The isomer shift and quadrupole splitting values show that FeA2+, FeA3+, FeB3+ and FeB2.5+ ions are present. FeB2.5+ represents the presence of the Fe2+ and Fe3+ ions on the B-sites, which take part in charge hopping. The results of electrical resistivity and magnetic measurements support charge hopping between Fe2+ and Fe3+ ions on B-sites.