X-ray powder diffraction and Mossbauer studies on the formation of Cd0.5Ni0.5Fe2O4/Zn0.5Ni0.5Fe2O4 spinel solid solutions

Structural investigations by X-ray powder diffraction, magnetic measurement s and by Mossbauer spectroscopy, applied to a series of solid solutions for med between two mixed spinels, zinc-nickel ferrite and cadmium-nickel ferri te, indicates the difference in the cation arrangement in the solid solutio n obtained hydrothermally, compared to that of ferrites sintered at high te mperatures. The ferrimagnetic crystalline Cd-Zn-Ni ferrite series, of a com position of Cd0.5-alphaZnalphaNi0.5Fe2O4, have been prepared by hydrotherma l treatment of the coprecipitated amorphous Cd-Zn-Ni-Fe hydroxide mixtures. The hydrothermally obtained samples displaying a defected spinel structure , with clearly noticeable non-stoichiometry, may be considered as precursor s for the preparation of stoichiometric products by further thermal treatme nt. The first approach to the Mossbauer spectra of the system (Cd0.5-alphaZ nalphaFe0.5)(tetr)[Ni0.5Fe1.5](oct)O-4 analysis has been undertaken. (C) 19 99 Elsevier Science Ltd. All rights reserved.