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arXiv · 2511.18526

Ab initio modeling of resonant inelastic x-ray scattering from Ca2RuO4

D. A. Kukusta·L. V. Bekenov·P. F. Perndorfer·D. V. Vyalikh·P. A. Buczek·A. Ernst·V. N. Antonov
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Abstract

The single-layered perovskite Ca$_2$RuO$_4$, characterized by a 4$d^4$ electron configuration, has been studied from first principles using density functional theory (DFT) using the generalized gradient approximation, with inclusion of strong on-site Coulomb interactions and spin-orbit coupling (GGA+SO+$U$), in the framework of the fully relativistic, spin-polarized Dirac linear muffin-tin orbital (LMTO) band-structure method. This approach enabled a comprehensive investigation of the electronic structure of Ca$_2$RuO$_4$ through the modeling of relevant spectra obtained from synchrotron-based techniques widely used to probe electronic properties, with a primary focus on resonant inelastic X-ray scattering (RIXS) at the Ru $L_3$ and O $K$ edges. The calculated spectra were thoroughly analyzed with available experimental data reported in the literature. The good agreement between our results and experimental observations for Ca$_2$RuO$_4$ enables a conclusive interpretation of key features in the spectra obtained from the aforementioned techniques. Consequently, this enables us to describe its electronic properties and to establish a solid theoretical approach suitable for routine modeling of spectra, particularly from RIXS, aimed at characterizing the electronic structure and properties of similar or more complex strongly correlated, technologically relevant materials.

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D. A. Kukusta, L. V. Bekenov, P. F. Perndorfer, D. V. Vyalikh, P. A. Buczek, A. Ernst, V. N. Antonov. 2025-11-23. Ab initio modeling of resonant inelastic x-ray scattering from Ca2RuO4. https://arxiv.org/abs/2511.18526

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