“Hard–Soft” Synthesis of SrCrO3−δ Superstructure Phases

Abstract

Dense metastable phases obtained under “hard” high-pressure conditions may contain instabilities such as unusual oxidation states or coordination environments that may be partially relieved by “soft” low-temperature chemistry. The synthesis of SrCrO2.8 (see picture, left) and SrCrO2.75 (right) phases from the high-pressure perovskite SrCrO3 leads to a relaxation of the coordination around Cr4+ from octahedral to tetrahedral.