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DOE OSTI · 1204244

Materials Data on Ba5Pt2O9 by Materials Project

Abstract

Ba5Pt2O9 crystallizes in the trigonal P321 space group. The structure is three-dimensional. there are five inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.76–3.04 Å. In the second Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Ba–O bond lengths are 2.67 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.62 Å) and three longer (2.65 Å) Ba–O bond lengths. In the fourth Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.84–2.87 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.86–3.18 Å. There are three inequivalent Pt4+ sites. In the first Pt4+ site, Pt4+ is bonded to six O2- atoms to form face-sharing PtO6 octahedra. There are three shorter (2.08 Å) and three longer (2.11 Å) Pt–O bond lengths. In the second Pt4+ site, Pt4+ is bonded to six O2- atoms to form face-sharing PtO6 octahedra. There are three shorter (2.05 Å) and three longer (2.11 Å) Pt–O bond lengths. In the third Pt4+ site, Pt4+ is bonded to six O2- atoms to form face-sharing PtO6 octahedra. There are three shorter (2.07 Å) and three longer (2.09 Å) Pt–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Ba2+ and one Pt4+ atom to form a mixture of distorted edge, corner, and face-sharing OBa5Pt octahedra. The corner-sharing octahedra tilt angles range from 10–66°. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Ba2+ and one Pt4+ atom. In the third O2- site, O2- is bonded to four Ba2+ and two equivalent Pt4+ atoms to form distorted OBa4Pt2 octahedra that share corners with six OBa5Pt octahedra, edges with two equivalent OBa4Pt2 octahedra, and faces with six OBa5Pt octahedra. The corner-sharing octahedra tilt angles range from 10–55°. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to five Ba2+ and one Pt4+ atom. In the fifth O2- site, O2- is bonded to four Ba2+ and two Pt4+ atoms to form distorted OBa4Pt2 octahedra that share corners with nine OBa5Pt octahedra, an edgeedge with one OBa4Pt2 octahedra, and faces with three OBa5Pt octahedra. The corner-sharing octahedra tilt angles range from 14–55°.

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2020-07-15. Materials Data on Ba5Pt2O9 by Materials Project. https://doi.org/10.17188/1204244

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36 MATERIALS SCIENCE↗