K-edge X-ray absorption spectra in transition metal oxides beyond the single particle approximation: shake-up many body effects

Abstract

The near edge structure (XANES) in K-edge X-ray absorption spectroscopy (XAS) is a widely used tool for studying electronic and local structure in materials. The precise interpretation of these spectra with the help of calculations is hence of prime importance, especially for the study of correlated materials which have a complicated electronic structure per se. The single particle approach, for example, has generally limited itself to the dominant dipolar cross-section. It has long been known however that effects beyond this approach should be taken into account, both due to the inadequacy of such calculations when compared to experiment and the presence of shake-up many-body satellites in core-level photoemission spectra of correlated materials. This effect should manifest itself in XANES spectra and the question is firstly how to account for it theoretically and secondly how to verify it experimentally. By using state-of-the-art first principles electronic structure calculations and 1s photoemission measurements we demonstrate that shake-up many-body effects are present in K-edge XAS dipolar spectra of NiO, CoO and CuO at all energy scales. We show that shake-up effects can be included in K-edge XAS spectra in a simple way by convoluting the single-particle first-principles calculations including core-hole effects with the 1s photoemission spectra. We thus describe all features appearing in the XAS dipolar cross-section of NiO and CoO and obtain a dramatic improvement with respect to the single-particle calculation in CuO. These materials being prototype correlated magnetic oxides, our work points to the presence of shake-up effects in K-edge XANES of most correlated transition metal compounds and shows how to account for them, paving the way to a precise understanding of their electronic structure.

6 pages, 4 pictures

References in corpus (5)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Bethe-Salpeter Equation Calculations of Core Excitation Spectra
• NiO: Correlated Bandstructure of a Charge-Transfer Insulator
• Revisiting the valence-band and core-level photoemission spectra of NiO
• Ab initio study of 2p-core level x-ray photoemission spectra in ferromagnetic transition metals

Cited by in corpus (11)

• Charge-transfer effect in hard x-ray 1$s$ and 2$p$ photoemission spectra: LDA+DMFT and cluster-model analysis
• Real time cumulant approach for charge transfer satellites in x-ray photoemission spectra
• Particle-hole cumulant approach for inelastic losses in x-ray spectra
• Quantum Many-Body Effects in X-Ray Spectra Efficiently Computed using a Basic Graph Algorithm
• A first-principle calculation of the XANES spectrum of Cu${}^{2+}$ in water
• Charge transfer satellites in x-ray spectra of transition metal oxides
• Ab initio multiplet plus cumulant approach for correlation effects in x-ray photoelectron spectroscopy
• Taming Convergence in the Determinant Approach for X-Ray Excitation Spectra
• Experimental assignment of many-electron excitations in the photo-ionization of NiO
• Satellites in the Ti~1$s$ core level spectra of SrTiO${}_3$ and TiO${}_2$
• Including atomic vibrations in XANES calculations: polarization-dependent damping of the fine structure at the Cu K edge of (creat)${}_2$CuCl${}_4$