High and ultra-high pressure research on phase transformations in 3d-metal oxides: current progress

Theory predicts that under a sufficient pressure magnetic systems with strong electron correlations undergo an insulator-metal phase transition which is accompanied by the collapse of the localized magnetic moment and also involves a structural phase transition. The pressures in question are, however, very high and hard to achieve, therefore until recently such scenario has not been observed experimentally. This paper reviews recent experimental studies of the influence of high and ultra-high pressures on the magnetic and crystal structure, the electronic and spin states, and the transport properties of 3d-metal oxides of different crystal structure