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DOE OSTI · 1720095

Materials Data on Ba2Er2Zn8O13 by Materials Project

Abstract

Ba2Er2Zn8O13 is Chalcostibite-derived structured and crystallizes in the monoclinic Cm 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 2.73–3.24 Å. In the second Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 3.01–3.33 Å. There are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to five O2- atoms to form ErO5 square pyramids that share corners with eight ZnO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.06–2.26 Å. In the second Er3+ site, Er3+ is bonded to six O2- atoms to form ErO6 octahedra that share corners with ten ZnO4 tetrahedra. There are a spread of Er–O bond distances ranging from 2.20–2.30 Å. There are six inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.88 Å) and one longer (1.98 Å) Zn–O bond length. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent ErO6 octahedra, a cornercorner with one ErO5 square pyramid, and corners with six ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There is one shorter (1.98 Å) and three longer (1.99 Å) Zn–O bond length. In the third Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with three equivalent ErO6 octahedra and corners with four ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are a spread of Zn–O bond distances ranging from 1.97–2.01 Å. In the fourth Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with three equivalent ErO5 square pyramids and corners with four ZnO4 tetrahedra. There are a spread of Zn–O bond distances ranging from 1.96–2.02 Å. In the fifth Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share a cornercorner with one ErO6 octahedra, corners with two equivalent ErO5 square pyramids, and corners with two ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Zn–O bond distances ranging from 1.95–2.01 Å. In the sixth Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent ErO6 octahedra, a cornercorner with one ErO5 square pyramid, and corners with six ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There is three shorter (1.97 Å) and one longer (1.98 Å) Zn–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to two Ba2+, one Er3+, and two Zn2+ atoms to form distorted OBa2ErZn2 trigonal bipyramids that share corners with two equivalent OZn4 tetrahedra and edges with two equivalent OBa2ErZn2 trigonal bipyramids. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Er3+, and two Zn2+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Er3+, and two Zn2+ atoms. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two Ba2+, one Er3+, and two equivalent Zn2+ atoms. In the fifth O2- site, O2- is bonded to four Zn2+ atoms to form corner-sharing OZn4 tetrahedra. In the sixth O2- site, O2- is bonded in a tetrahedral geometry to four Zn2+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Er3+, and two Zn2+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Er3+, and two Zn2+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Er3+, and two Zn2+ atoms.

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2020-04-30. Materials Data on Ba2Er2Zn8O13 by Materials Project. https://doi.org/10.17188/1720095

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