Fig. 1: Illustration of the concept of the present study.
a The correlation between local elemental distribution, atomic structure, chemical bonding, and magnetic properties. b Schematic crystallographic structure of LaCoO3. c Rhombohedral LaCoO3 parent structure (bottom left) with negligible oxygen octahedral distortion and orthorhombic model of high-entropy oxide (top right) with uniformly distributed elements and oxygen octahedral distortion (as that derived from XRD pattern). d Compositional fluctuation with nanometer-scale ordering and composition-dependent local oxygen octahedral distortion of the high-entropy perovskite oxide that we observed in the present study. In (c) and (d), most of the oxygen atoms overlapped with A-site La atoms are omitted for visual clarity, and only those oxygen atoms belonging to the marked oxygen octahedra are present. Local chemical composition fluctuation of transition metal at each B-site atomic column gives rise to the different degree of local oxygen octahedral distortion, as indicated by the varied TM–O–TM bonding angle marked between the B-site atomic columns and the oxygen ones.
