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DOE OSTI · 1267918

Materials Data on Ba2Sb4P2O17 by Materials Project

Abstract

Ba2Sb4O9(PO4)2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.76–3.08 Å. In the second Ba2+ site, Ba2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Ba–O bond distances ranging from 2.57–2.70 Å. There are three inequivalent Sb5+ sites. In the first Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with five SbO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–49°. There are a spread of Sb–O bond distances ranging from 1.96–2.11 Å. In the second Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four equivalent SbO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–49°. There are a spread of Sb–O bond distances ranging from 1.97–2.05 Å. In the third Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four SbO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–47°. There are a spread of Sb–O bond distances ranging from 1.97–2.05 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three SbO6 octahedra. The corner-sharing octahedra tilt angles range from 41–42°. There is one shorter (1.50 Å) and three longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three SbO6 octahedra. The corner-sharing octahedra tilt angles range from 52–55°. There are a spread of P–O bond distances ranging from 1.51–1.58 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sb5+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and two Sb5+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and two equivalent Sb5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+ and two Sb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sb5+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Sb5+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Sb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sb5+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to two Ba2+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and two Sb5+ atoms. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Sb5+, and one P5+ atom.

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2020-05-31. Materials Data on Ba2Sb4P2O17 by Materials Project. https://doi.org/10.17188/1267918

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36 MATERIALS SCIENCE↗