No 2, Vol. 12, 2006, pages 178-181


G. Zolnierkiewicz, N. Guskos, J. Typek and E. Tomaszewicz


Three gadolinium(III) tungstates (II-Gd2WO6, CoGd4W3O16, and ZnGd4W3O16) have been prepared by the solid-state reaction method using stoichiometric mixtures of the WO3, Gd2O3, CoWO4 or ZnWO4. The EPR measurements have been done at room temperature for all three samples. A very intense asymmetric EPR line of gadolinium(III) ions has been recorded. The intensity and the linewidth essentially depended on the metal (M(II)=Co(II) and Zn(II)) ions in the crystalline matrix. The difference of the linewidth and intensities is arising from magnetic interactions between magnetic ions, especially for the system with coexisting two different magnetic ions. It was estimated that the exchange field in the II-Gd2WO6 and α -Fe2WO6 systems is similar but differs significantly in its polymorphic modification. For new divalent metal and gadolinium(III) tungstates (CoGd4W3O16 and ZnGd4W3O16) the exchange field is modified by about 6% after substitution of metal(II) magnetic ions for a non magnetic ion.

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