Order, Disorder, and Dynamics in Brownmillerite Sr2Fe2O5

Auckett, Josie E.; Lee, Wai Tung; Rule, Kirrily C.; Bosak, Alexey; Ling, Chris D.

Abstract

The room-temperature structure of brownmillerite-type Sr2Fe2O5 remains controversial, despite numerous published crystallographic studies utilizing X-ray, neutron, and electron diffraction data collected on single-crystalline and powder samples. The main disagreements concern the ordering of twisted FeO4 tetrahedral chains within and between the layers stacked along the b axis, and the impact of this ordering on oxide-ionic conductivity. Here, we present new data along with a reinterpretation of previously published diffraction images, including the reassignment of satellite reflections, which harmonize the results of past studies in a unified description of tetrahedral chain ordering in Sr2Fe2O5 at length scales relevant to X-ray and neutron diffraction. Implications for the prevailing model of oxide ion transport in this material are also discussed.

Citation

Auckett, J. E., Lee, W. T., Rule, K. C., Bosak, A., & Ling, C. D. (2019). Order, Disorder, and Dynamics in Brownmillerite Sr2Fe2O5. Inorganic Chemistry, 58(18), 12317-12324. https://doi.org/10.1021/acs.inorgchem.9b01846

• Journal Article Type: Article
• Acceptance Date: Aug 9, 2019
• Online Publication Date: Aug 23, 2019
• Publication Date: Sep 16, 2019
• Deposit Date: Sep 17, 2019
• Publicly Available Date: Aug 23, 2020
• Journal: Inorganic Chemistry
• Print ISSN: 0020-1669
• Electronic ISSN: 1520-510X
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 58
• Issue: 18
• Pages: 12317-12324
• DOI: https://doi.org/10.1021/acs.inorgchem.9b01846
• Public URL: https://durham-repository.worktribe.com/output/1291438