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Information × Registration Number 0219U006074, 0118U005163 , R & D reports Title The atomic disordering effects and their influence on a phase stability, an electronic structure and the physical properties of the Heusler alloys popup.stage_title Head Uvarov Viktor Mykolayovych, Доктор фізико-математичних наук Registration Date 04-04-2019 Organization Institute for metal physics NAS Ukkraine popup.description2 The study of spatial and electronic structure, optical and magnetic properties of the non-stoichiometric alloys Heusler Fe2MnGa phases samples (in L21 and L12- structural types with the different types of magnetic ordering), using the methods of the spectral ellipsometry, magnetometry, X-ray diffraction analysis and the calculations of the band structure ( in the FLAPW model) were carried out. Comparison of the calculated data with the results of experimental studies of the created alloys enable for us to fit the bands of interband absorption of electron excitation between certain electron states in spin subsystems both in along and in against of the resulting magnetization. Structural L21 to L12 (or bcc to fcc) transformations are found to cause the significant changes in the magnetic properties of massive samples. At the same time, the magnetic properties, in practice, have no influence on the optical properties of alloys. Using the above-mentioned zonal calculations, the role of mutual atomic substitutions in formation of energy, charge and spin characteristics of alloys MMnSb (M = Co, Ni, Cu) has been clarified. It was established that the decrease of the covalentness of chemical bonds and the associated decrease in the values of cohesive energies, with the growth of the atomic number of M-metals in MMnSb alloys (M = Co, Ni, Cu), stimulates the processes of atomic disordering in them and correlates with the associated growth of them specific resistance. Product Description popup.authors Клімов Володимир Вікторович Кудрявцев Юрій Володимирович Мельник Максим Петрович Немошкаленко Марина Володимірівна popup.nrat_date 2020-04-02 Close