Structure-Property Relationship in the Ordered-Perovskite- Related Oxide Sr3.12Er0.88Co4O10.5

TL;DR

This study investigates the structural phase transitions and magnetic properties of Sr3.12Er0.88Co4O10.5 using synchrotron X-ray diffraction, revealing two phase transitions linked to oxygen vacancy ordering and ferromagnetism.

Contribution

It provides detailed analysis of phase transitions and proposes models for magnetic order in the ordered-perovskite-related oxide Sr3.12Er0.88Co4O10.5.

Findings

Two structural phase transitions at 509 K and 360 K.

Oxygen vacancy ordering influences metallic state.

Ferromagnetic state appears suddenly at 360 K.

Abstract

Synchrotron X-ray diffraction patterns were measured and analyzed for a polycrystalline sample of the room-temperature ferromagnet Sr3.12Er0.88Co4O10.5 from 300 to 650 K, from which two structural phase transitions were found to occur successively. The higher-temperature transition at 509 K is driven by ordering of the oxygen vacancies, which is closely related to the metallic state at high temperatures. The lower-temperature transition at 360 K is of first order, at which the ferromagnetic state suddenly appears with exhibiting a jump in magnetization and resistivity. Based on the refined structure, possible spin and orbital models for the magnetic order are proposed.