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Information × Registration Number 0225U004745, (0125U003444) , R & D reports Title Resonant inelastic x-ray scattering in complex 5d oxides from first principles popup.stage_title Резонансне непружне Рентгенове розсіювання в оксиді Ca2RuO4 Head Antonov Viktor M., Доктор фізико-математичних наук Registration Date 18-12-2025 Organization Institute of Metal Physics. G.V. Kurdyumov of the National Academy of Sciences of Ukraine popup.description1 To obtain theoretically from first principles within the density-functional theory (DFT) taking into account strong Coulomb correlations (DFT+U) fundamental knowledge about the electronic structure, magnetic properties, and resonant inelastic X-ray scattering (RIXS) of some complex oxides, in which unconventional quantum phases of matter can arise due to the interplay of strong spin-orbit interaction and electronic correlations. popup.description2 Based on DFT and DFT+U calculations, theoretical studies of the electronic structure and magnetic properties as well as Ru L3 and O K spectra of resonant inelastic X-ray scattering (RIXS) of the oxide Ca2RuO4 have been carried out. The influence of spin-orbit coupling (SOC) and strong Coulomb correlations on the character of its ground state has been analyzed. The ground state magnetic structure of Ca2RuO4 has been shown to be noncollinear antiferromagnetic. The calculations have revealed that the energy gap in Ca2RuO4 opens up due to the interplay of SOC and Coulomb electron-electron correlations. However, magnetic ordering also plays an important role in the formation of the gap in Ca2RuO4. Consequently, this oxide exhibits a mixed Mott (electronic correlations) and Slater (magnetic ordering) insulating character. It has been found that the Ru t2g density of states in the vicinity of the Fermi level has two peaks just below the Fermi level and one peak just above the Fermi level. These peaks have been demonstrated to play a key role for the Ru L3 and O K RIXS spectra in Ca2RuO4. The best agreement between the calculated DFT+U RIXS spectra and experimentally obtained ones has been achieved using the effective Hubbard parameter Ueff = 0.5 eV. The calculations have revealed strong dependence of the Ru L3 and O K RIXS spectra on the incident photon energy and strong polarization dependence of the Ru L3 RIXS spectrum. Product Description popup.authors Lev V. Bekenov Denys О. Kukusta popup.nrat_date 2025-12-18 Close