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Information × Registration Number 0221U104073, 0116U003053 , R & D reports Title The structure and properties materials for spintronic and sensoric devices on the transition metall base. popup.stage_title Head Uvarov Viktor M., Доктор фізико-математичних наук Registration Date 02-03-2021 Organization Institute of Metal Physics. G.V. Kurdyumov of the National Academy of Sciences of Ukraine popup.description2 Using the methods of computer modeling for the spatial structure of compounds, methods of X-ray, X-ray electron, optical, magneto-optical, EPR spectroscopy, magnetometry, as well as calculations of their electronic structure in the band approximation allowed to obtain many valuable new results. In particular, it helped to reveal role of local partial electronic states in the formation of valence bands and the participation of them for the formation of chemical bonds in different crystal symmetry, to get the total and partial charge of atomic states and that was part of the studies for Geisler's phases. Decided that structure of valence bands significant depends on the atomic composition and symmetry of their crystal lattices. First time get it the effects of atomic disruptions on energy bonds and certain features of chemical interatomic interactions, this effect react on the magnetic characteristics of Geisler's alloys too. It was decided that the bond energies increase in the sequence of PdMnSb-NiMnSb-PtMnSb alloys due to the growth of the covalent interaction of atoms, which is confirmed by resistive measurements. The influence of martensitic L21 → L10 transformation in Geisler's Fe2MnGa alloy on its electronic structure and physical properties has been studied in detail. It is established that preliminary heat treatment of this alloy allows to fix austenitic or martensitic phase with corresponding properties at room temperature, and also it is shown that increase of electric resistance and change of sign of temperature coefficient of resistance at transition to austenitic phase are caused by changes in density of electronic states. It was found that, magnetoresistive effect for the parallel orientation of the external magnetic field relative to the atomic layers, in Bi93.99Mn6Fe0.01 crystals is 6 times greater than for the perpendicular orientation of the field. Product Description popup.authors Klimov Vladimir V. Kudryavtsev Yuri V. Melnik Maxim P. Nemoshkalenko Maryna V. Shevchenko Anatoliy D. popup.nrat_date 2021-03-02 Close