The Mott insulators at extreme conditions; structural consequences of pressure-induced electronic transitions

Gregory Kh. Rozenberg 1 , Weiming Xu 2  and Moshe P. Pasternak 3
  • 1 School of Physics and Astronomy, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel
  • 2 School of Physics and Astronomy, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel
  • 3 School of Physics and Astronomy, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel

Abstract

Electronic/magnetic transitions and their structural consequences in Fe-based Mott insulators in a regime of very high static density are the main issue of this short review paper. The paper focuses on the above-mentioned topics based primarily on our previous and ongoing experimental HP studies employing: (i) diamond anvil cells, (ii) synchrotron X-ray diffraction, (iii) 57Fe Mössbauer spectroscopy, (iv) electrical resistance and (v) X-ray absorption spectroscopy. It is shown that applying pressure to such strongly correlated systems leads to a number of changes; including quenching of the orbital moment, quenching of Jahn-Teller distortion, spin crossover, inter-valence charge transfer, insulator–metal transition, moment collapse and volume collapse. These changes may occur simultaneously or sequentially over a range of pressures. Any of these may be accompanied by or be a consequence of a structural phase transition; namely, a change in crystal symmetry. Analyzing this rich variety of phenomena we show the main scenarios which such strongly correlated systems may undergo on the way to a correlation breakdown (Mott transition). To illustrate these scenarios we present recent results for MFeO3 (M = Fe, Ga, Lu, Eu, Pr) and CaFe2O4 ferric oxides; FeCl2 and FeI2 ferrous halides, and FeCr2S4 sulfide. Fe3O4 is given as an example case for the impact of Mössbauer Spectroscopy on High Pressure Crystallography studies.

If the inline PDF is not rendering correctly, you can download the PDF file here.

OPEN ACCESS

Journal + Issues

Zeitschrift für Kristallographie – Crystalline Materials offers a place for researchers to present results of their crystallographic studies. The journal includes theoretical as well as experimental research. It publishes Original Papers, Letters and Review Articles in manifold areas of crystallography.

Search