Solokha P. Interaction of the components in Tb-{Fe, Ni, Cu}-{Zn, Mg} ternary systems and related to them (phase equilibria, crystal structure and physical properties of compounds)

The isothermal sections (400 °С or 200 °С) of Tb-{Fe, Ni, Cu}-{Mg, Zn}, La-Ni-Zn, Ce-Cu-Zn phase diagrams in the whole concentration range were constructed by means of X-ray phase, X-ray structural and microstructure analyses. The existence of 7 known and 47 new ternary phases was found in these systems. The crystal structure of 37 compounds (among them the isostructural series RCu9Mg2) was studied by means of X-ray single crystal and powder diffraction methods. Investigated compounds belong to 17 structure types; five of them represent new structure types: La7Ni2Zn, TbCu9Mg2, TbCuMg4, Tb2Ni2Mg3, TmCu4,40Mg0,76. Crystallochemical relations of novel compounds with known structure types were established. The magnetic susceptibility vs. temperature and magnetization curves was studied for some intermetallics. It was determined, that TbCu9Mg2 is a Curie-Weiss paramagnet, Tb2Cu2Mg is a ferromagnetic (ТС=80 К), TbNiZn, Tb2Ni2Zn15, Tb2Ni2Mg3 and Tb3Ni2Mg20 are antiferromagnetics (TN=13, 45, 47 та 18 К, respectively). The presence of terbium atoms (Tb3+) causes magnetic properties of these compounds. Electrochemical testing of LaCu9Mg2, LaNi9Mg2 and TbNi9Mg2 as anode materials in batteries was performed. They possess high discharge capacities (up to 320 mA·h/g), alloy electrodes exhibit a good activation rate, that make possible to adopt them in batteries.