The importance of inter-site coherences in the x-ray absorption spectra of mixed-valent systems

Abstract

We study the importance of inter-site coherences and quantum interference effects in the x-ray absorption spectroscopy (XAS) of mixed-valent systems. We demonstrate its importance, first for a simple diatomic mixed-valent molecule to elucidate the physics involved, and finally for mixed-valent Ti oxides, using a model calculation including full spin and orbital multiplicities. Our calculations demonstrate the inefficacy of conventional approaches of describing the XAS from mixed-valent systems as incoherent combinations of XAS from the pure-valent end members, and that multiplets forbidden in the single-site approximation can be reached within a multi-site description. These conclusions play an important role in the interpretation of XAS and resonant x-ray scattering (RXS) in terms of the electronic structure of strongly correlated systems.

7 pages, 6 figures, Submitted to Europhysics Letters

References in corpus (3)

• The Mott insulator LaTiO_3 in heterostructures with SrTiO_3 is metallic
• Spin-Flop Ordering from Frustrated Ferro- and Antiferromagnetic Interactions: A Combined Theoretical and Experimental Study of a $\mathrm{Mn}/\mathrm{Fe}(100)$ Monolayer
• Electronic structure of the SrTiO${}_3$/LaAlO${}_3$ interface revealed by resonant soft x-ray scattering

Cited by in corpus (2)

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• Spectral Weight Transfer in Multi-Orbital Mott Systems