ABSTRACT
Materials based on new compounds with pyrochlore structure type show a variety of areas of their practical use, including the ability of individual compounds to immobilize actinides, catalysis, ferromagnetism, dielectric properties, and mixed ion conductivity. The magnetic behavior data for mixed niobates and bismuth titanates with layered perovskite structure are scarce and incomplete. The dilution of layered iron-containing bismuth titanates results in a complete disaggregation of iron atoms. In layered bismuth niobates, even at the infinite dilution, ferromagnetic dimers along with single iron atoms seem to be preserved. Based on the structural, spectroscopic and magnetochemical study of doped bismuth titanates and niobates containing 3d-elements—chromium, iron, manganese, the following trends are revealed. The magnetic behavior of solid solutions based on bismuth titanate and bismuth niobate with pyrochlore-type structure is determined by the distribution of paramagnetic atoms over two cationic sites of the structure.
