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DOE OSTI · 1288891

Materials Data on TbBi5O9 by Materials Project

Abstract

TbBi5O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. Tb3+ is bonded to seven O2- atoms to form distorted TbO7 hexagonal pyramids that share corners with two equivalent BiO5 trigonal bipyramids, edges with two equivalent TbO7 hexagonal pyramids, and an edgeedge with one BiO4 trigonal pyramid. There are a spread of Tb–O bond distances ranging from 2.36–2.42 Å. There are five inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.21–2.45 Å. In the second Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.28–2.74 Å. In the third Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Bi–O bond distances ranging from 2.27–3.09 Å. In the fourth Bi3+ site, Bi3+ is bonded to four O2- atoms to form distorted BiO4 trigonal pyramids that share corners with two equivalent BiO4 trigonal pyramids and an edgeedge with one TbO7 hexagonal pyramid. There are a spread of Bi–O bond distances ranging from 2.15–2.33 Å. In the fifth Bi3+ site, Bi3+ is bonded to five O2- atoms to form distorted BiO5 trigonal bipyramids that share corners with two equivalent TbO7 hexagonal pyramids and corners with two equivalent BiO5 trigonal bipyramids. There are a spread of Bi–O bond distances ranging from 2.17–2.61 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to four Bi3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to four Bi3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to four Bi3+ atoms. In the fourth O2- site, O2- is bonded to two equivalent Tb3+ and two Bi3+ atoms to form OTb2Bi2 tetrahedra that share corners with seven OTb2Bi2 tetrahedra and edges with four OTbBi3 tetrahedra. In the fifth O2- site, O2- is bonded to one Tb3+ and three Bi3+ atoms to form distorted OTbBi3 tetrahedra that share corners with six OTbBi3 tetrahedra and edges with five OTb2Bi2 tetrahedra. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Tb3+ and one Bi3+ atom. In the seventh O2- site, O2- is bonded to four Bi3+ atoms to form OBi4 tetrahedra that share corners with five OTb2Bi2 tetrahedra and edges with two equivalent OTbBi3 tetrahedra. In the eighth O2- site, O2- is bonded to one Tb3+ and three Bi3+ atoms to form distorted OTbBi3 tetrahedra that share corners with three OTbBi3 tetrahedra and edges with three OTb2Bi2 tetrahedra. In the ninth O2- site, O2- is bonded to one Tb3+ and three Bi3+ atoms to form OTbBi3 tetrahedra that share corners with eleven OTb2Bi2 tetrahedra and edges with two OTbBi3 tetrahedra.

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2020-07-18. Materials Data on TbBi5O9 by Materials Project. https://doi.org/10.17188/1288891

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