Metal-ligand interplay in strongly correlated oxides: a parametrized phase diagram for pressure-induced spin transitions.
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 Kbeta line. 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 spectral changes are well accounted for by changes of the ligand field acting on the d electrons and allows us to extract the d-hybridization strength, O-2p bandwidth and ionic crystal field across the magnetic transition. This approach allows first-hand insight into the mechanism of the pressure-induced spin transition.
Mattila
Aleksi
A
Division of X-Ray Physics, Department of Physical Sciences, POB 64, 00014 University of Helsinki, Finland.
Rueff
Jean-Pascal
JP
Badro
James
J
Vankó
György
G
Shukla
Abhay
A