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DOE OSTI · 1204582

Materials Data on Sr7Re4O19 by Materials Project

Abstract

Sr7Re4O19 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with three equivalent SrO12 cuboctahedra, corners with three ReO6 octahedra, faces with five SrO12 cuboctahedra, and faces with four ReO6 octahedra. The corner-sharing octahedra tilt angles range from 17–18°. There are a spread of Sr–O bond distances ranging from 2.63–3.08 Å. In the second Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–3.01 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with two equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, and faces with six ReO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.73–2.82 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.93 Å. There are two inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with two equivalent SrO12 cuboctahedra, corners with three ReO6 octahedra, and faces with four SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Re–O bond distances ranging from 1.89–1.99 Å. In the second Re6+ site, Re6+ is bonded to six O2- atoms to form ReO6 octahedra that share a cornercorner with one SrO12 cuboctahedra, corners with two equivalent ReO6 octahedra, and faces with three SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 9°. There are a spread of Re–O bond distances ranging from 1.85–2.02 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Re6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Re6+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Re6+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to four Sr2+ and one Re6+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Re6+ atom. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to four Sr2+ and one Re6+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+ and two Re6+ atoms.

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2020-07-20. Materials Data on Sr7Re4O19 by Materials Project. https://doi.org/10.17188/1204582

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