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DOE OSTI · 1654180

Materials Data on Ba2Tm2Zn8O13 by Materials Project

Abstract

Ba2Tm2Zn8O13 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 2-coordinate geometry to eight O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.35 Å. In the second Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.78–3.00 Å. There are two inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to five O2- atoms to form TmO5 square pyramids that share corners with eight ZnO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.07–2.26 Å. In the second Tm3+ site, Tm3+ is bonded to six O2- atoms to form TmO6 octahedra that share corners with ten ZnO4 tetrahedra. There are a spread of Tm–O bond distances ranging from 2.20–2.33 Å. There are six inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share a cornercorner with one TmO6 octahedra, corners with two equivalent TmO5 square pyramids, and corners with five ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Zn–O bond distances ranging from 1.96–2.02 Å. In the second Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with two equivalent TmO6 octahedra, a cornercorner with one TmO5 square pyramid, and corners with three ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Zn–O bond distances ranging from 1.97–2.00 Å. In the third Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with three equivalent TmO6 octahedra and corners with five ZnO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are three shorter (1.97 Å) and one longer (2.05 Å) Zn–O bond lengths. In the fourth Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.90 Å) and one longer (1.94 Å) Zn–O bond length. In the fifth Zn2+ site, Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share a cornercorner with one TmO6 octahedra, corners with two equivalent TmO5 square pyramids, and corners with five ZnO4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Zn–O bond distances ranging from 1.97–2.04 Å. In the sixth Zn2+ site, Zn2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.90 Å) and one longer (1.93 Å) Zn–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to four Zn2+ atoms to form corner-sharing OZn4 tetrahedra. In the second O2- site, O2- is bonded to four Zn2+ atoms to form corner-sharing OZn4 tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Tm3+, and two Zn2+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Tm3+, and two equivalent Zn2+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Tm3+, and two equivalent Zn2+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Ba2+, one Tm3+, and two Zn2+ atoms. In the seventh O2- site, O2- is bonded to one Ba2+, one Tm3+, and two Zn2+ atoms to form distorted OBaTmZn2 tetrahedra that share corners with six OZn4 tetrahedra and an edgeedge with one OBaTmZn2 tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, one Tm3+, and two Zn2+ atoms. In the ninth O2- site, O2- is bonded to one Ba2+, one Tm3+, and two Zn2+ atoms to form distorted OBaTmZn2 tetrahedra that share corners with six OZn4 tetrahedra and an edgeedge with one OBaTmZn2 tetrahedra.

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2020-07-15. Materials Data on Ba2Tm2Zn8O13 by Materials Project. https://doi.org/10.17188/1654180

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