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Information × Registration Number 0222U003193, 0119U100732 , R & D reports Title New oxide multiferroics: role of oxygen vacancies and frustrated magnetism in created of particular properties popup.stage_title Head Glinchuk Maya D., Доктор фізико-математичних наук Registration Date 21-02-2022 Organization Institute of Problems of Materials Science named after IM Frantsevich of the National Academy of Sciences of Ukraine popup.description2 Using the Landau-Ginzburg-Devonshire phenomenological approach and the semi-microscopic model of four sublattices, the regions of different phases existence were established: antiferroelectric, ferrielectric and ferroelectric, as well as their coexistence areas and relative parts at morphotropic boundaries in antiferrodistortive multiferroics. Theoretical modeling of polarization reversal processes in ferroelectric thin films and domain structure formation has been carried out, it has been established that the flexoeffect promotes the polarization reversal process. The influence of surface shielding charges on the parameters of the domain structure, phase diagrams of ferroelectrics and temperature dynamics of hysteresis loops is determined. Quantitative characteristics of the influence of physical factors on the processes of polarization reversal in ferroelectric films are obtained. The application of antiferroelectric films coated with the surface ion layer for energy and information storage has been studied. It has been developed a method for calculating ligand field parameters and multiplet spectra of local magnetic centers with partially filled d- and f-electron shells, which does not require fitting parameters. The results of experiments on inelastic neutron scattering of the oxide compound Ca2Y2Cu5O10 are analyzed. Simulation of excitations using the theory of spin waves made it possible to find the values of exchange integrals, which allowed us to calculate the magnetic susceptibility of the material. Using Keldysh's formalism for nonequilibrium systems within the one-stage theory of photoemission, formulas for the time of escape of a photoelectron from a material are obtained. The formulas were implemented in computer DFT code. Product Description popup.authors Eliseev Eugene A Kondakova Iryna V Kuzian Roman O. Likhtin Andrіy E Laguta Valentin V. Roginets Nadia V Yurchenko Lesia Р popup.nrat_date 2022-03-09 Close