Phase Formation in REE-Containing Water-Salt Systems at the Preparatory Stages of the ulticomponent Oxide Functional Materials Formation

Using a number of physico-chemical methods, the authors have studied the nature and laws of chemical interaction between structural components, heterogeneous equilibrium (25-100 оC) in model triple water-salt systems of sulphates, nitrates, chlorides neodymium and alkali metals. Complicated processes of complex formation in creations the entire classes of anionic Ln3+ complexes have been determined. Polythermal solubility diagrams have been built for the studied systems. Conditions for the source materials and new phase existence are clarified. Optimal growth conditions have been determined, and synthesis of single-crystal samples has been carried out. A number of physical and chemical properties are studied, and the individuality of double salts has been confirmed. A number of features and usage patterns were revealed in transformations. The obtained results are treated as a reliable scientific basis for substantiation of preparatory process in the up-to-date REE-containing functional materials production.