Medium-range structure motifs of complex iron oxides

Natural occurring iron oxides, such as Fe2O3, Fe3O4, and FeO, are abundant on Earth's surface feature many implications in our daily life since the Iron Age, final epoch of prehistory humanity. The physics oxides is at frontier physical research due to their complicated magnetic electronic properties. What makes it even more intriguing introduction pressure, which not only regulates crystal structures properties, but also creates new iron-oxide stoichiometry. Recent studies discovered several novel iron-oxygen compounds under various pressure–temperature conditions. Despite different Fe/O ratios, those built upon similar structural units including FeO6 octahedra trigonal prisms. Complex stoichiometry pressurized up by stacking layers units, medium-range, they organized certain motifs. In this perspective, we go beyond conventional binary reveal general formation mechanism complex oxide crystals high-pressure results will be helpful for summarizing literary works exploring with optimal