Abstract
Structural aspects of magnetic/electronic transitions in strongly correlated systems in a regime of very high static density are the main issues of this article. To achieve this objective, we have carried out series of X-ray diffraction (XRD) measurements up to 120 GPa using diamond anvil cells (DACs) to probe structural features specifically related to pressure-induced (PI) magnetic/electronic phenomena in transition metal (TM) compounds. The types of phenomena are the Mott transition (MT), high-spin (HS) to low-spin (LS) transition, valence transformations, the quenching of the orbital term, and Verwey transition. In all these cases, the electronic transition may induce or be a consequence of structural alterations. These studies provide essential information concerning: (i) structural alterations attributed to the valence transformation in some TM compounds; (ii) mechanisms and precursors responsible for the PI MT; features of the structural transformation specifically attributed to the MT for different types of the electronic transitions (Mott-Hubbard and Charge-Transfer); (iii) the mechanism of the PI degradation of the magnetic state due to HS-LS transition and their influence on the structural properties of material; (iv) mechanism of Verwey transition in magnetite; (v) structure of new phases at high pressure. As example cases we present recent results in some Fe-oxides, halides, and sulfides.
Original language | English |
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Pages (from-to) | 1131-1150 |
Number of pages | 20 |
Journal | Phase Transitions |
Volume | 80 |
Issue number | 10-12 |
DOIs | |
State | Published - Oct 2007 |
Keywords
- Electronic/magnetic transitions
- High pressure
- Strongly correlated systems
- X-ray crystallography