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Information × Registration Number 0210U005705, 0106U000682 , R & D reports Title Influence of crystall chemical features, temperatures and pressures on the isomorphism of transition elements of the iron group in the rock-forming minerals of magmatic and metamorphic origin. popup.stage_title Head Ponomarenko O.M., Registration Date 04-01-2011 Organization M.P. Semenenko Institute of Geochemistry, mineralogy and Ore Formation popup.description2 By a series of spectroscopic methods such transition metal ions as predominantly Ti4+, Cr3+, Fe2+, Fe3+ have been studied as they constitute the main part of the transition elements which participate in many mineral- and rock-forming processes influencing coloration, thermo- and electric conductivity and other properties of minerals, rocks, geological formations or even entire geological landscapes. Due to electronic configuration and spectroscopic features, Cr3+ was used as an original model ion, especially at investigation of the influence of temperature and pressure on dimension and local symmetry of structural Cr3+-centered octahedra, chemical bond character, the phenomenon of local structure relaxation and deviations from Vegard's rule, the effect of pressure to solubility of Cr3+ in natural solid solutions, clusterization at isomorphic substitution and so on. By the methods of Fourier IR-spectroscopy the effect of Mg, Fe2+-ordering in thermally treated olivines and spectroscopic display of this phenomenon in natural olivines of various origins were studied. It was established that there exists a weak ordering of ferrous ions in either M1 or M2 structural positions, the effect which is most probably caused by a speed of cooling of the samples after crystallization. On the basis of experimentally measured dependences of Ti-concentration on crystallization temperature on different pressures a new rutile-quartz thermobarometer was induced, which may be implied for evaluation of the PT-conditions of crystallization of quartz-bearing rocks. Product Description popup.authors Платонов Олексій Миколайович Таран Михайло Миколайович Таращан Аркадій Миколайович Хоменко Володимир Михайлович popup.nrat_date 2020-04-02 Close