Local structure change around Co and Fe ions in (La0.6Sr0.4)(Co0.2Fe0.8)O3−δ as revealed by in-situ X-ray absorption spectroscopy and first-principles calculation

Conceptual models of (La0.6Sr0.4)(Co0.2Fe0.8)O3−δ structure (a) without and (b) with oxygen ion vacancies. 271