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Metal-ligand interplay in strongly-correlated oxides: a parametrized phase diagram for pressure induced spin transitions

A. Mattila·J. -P. Rueff·J. Badro·G. Vanko·A. Shukla
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Abstract

We investigate the magnetic properties of archetypal transition-metal oxides MnO, FeO, CoO and NiO under very high pressure by x-ray emission spectroscopy at the Kβline. We observe a strong modification of the magnetism in the megabar range in all the samples except NiO. The results are analyzed within a multiplet approach including charge-transfer effects. The pressure dependence of the emission line is well accounted for by changes of the ligand field acting on the d electrons and allows us to extract parameters like local d-hybridization strength, O-2p bandwidth and ionic crystal field across the magnetic transition. This approach allows a first-hand insight into the mechanism of the pressure induced spin transition.

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A. Mattila, J. -P. Rueff, J. Badro, G. Vanko, A. Shukla. 2006-12-07. Metal-ligand interplay in strongly-correlated oxides: a parametrized phase diagram for pressure induced spin transitions. https://doi.org/10.1103/physrevlett.98.196404

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