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Information × Registration Number 0222U001948, 0117U002132 , R & D reports Title Electronic structure and magnetic properties of complex transition metal oxides and heterostructures popup.stage_title Head Antonov Viktor M., Доктор фізико-математичних наук Registration Date 04-02-2022 Organization Institute of Metal Physics. G.V. Kurdyumov of the National Academy of Sciences of Ukraine popup.description2 On the basis of density functional theory (DFT) calculations by the fully relativistic linear MT orbital band method using the local spin density approximation (LSDA), generalized gradient approximation (GGA) and LSDA/GGA+U approach, which takes into account Coulomb electron correlations, fundamental knowledge about the electronic structure, magnetic and other physical properties of complex transition metals oxides and heterostructures, such as BaFeO3-d (0 ≤ d ≤ 0.5), Sr2FeMO6, A2FeReO6 (A = Ba, Sr, Ca), A2CrB'O6 (A = Ca, Sr; B' = W, Re, Os), Sr2CrReO6/BaTiO3, the 4f compounds SmRh2Si2 and YbNiSn, the iridates b-Li2IrO3 and Pr2Ir2O7, has been gained. Their X-ray absorption, X-ray magnetic circular dichroism and resonant inelastic X-ray scattering spectra have been theoretically obtained, analyzed and explained. It has been found that O vacancies in BaFeO3 can significantly reduce its Curie temperature or even change the ferromagnetic ordering to the antiferromagnetic or non-collinear one. The theoretical predictions about Sr2FeMO6 are consistent with experimental data only if correlation effects and the presence of oxygen vacancies are taken into account. Correlation effects on Fe in A2FeReO6 (A = Ba, Sr, Ca) increase with the Ba>Sr>Ca change. Correlations on Re are small in compounds based on Ba and Sr, but significant in Ca2FeReO6. The mixed valence of both surface and bulk Sm atoms in SmRh2Si2, which is quite unusual for most Sm-based materials, is due to strong 4f hybridization. The formation of a coherent state at 10 K, which is found in experiments on the transport properties of YbNiSn, should be separated from the formation of renormalized zones and the beginning of the Kondo lattice formation, which occurs at much higher temperatures. In b-Li2IrO3 due to the subtle interplay between the spin-orbit coupling, intermetallic bonding and magnetism the structural transition that occurs with increasing pressure can lead to the formation of Ir-Ir dimers. Product Description popup.authors Bekenov Lev V. Zhuravlyov Boris H. Zenina Irina B. Kovalchuk Galyna I. Kukusta Denys О. Kucherenko Yuri N. Mazur Dmytro V. Moklyak Sergiy V. Sirenko V. T. Sichkar Sergey M. Sulʹzhenko Valeriy К. Uvarov Mykola V. popup.nrat_date 2022-03-09 Close