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DOE OSTI · 1301442

Materials Data on Na3SiBiBO7 by Materials Project

Abstract

Na3BSiBiO7 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.43–2.86 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.26–2.60 Å. B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.34–1.43 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–62°. All Si–O bond lengths are 1.65 Å. Bi is bonded to six O atoms to form BiO6 octahedra that share corners with four equivalent SiO4 tetrahedra. There are a spread of Bi–O bond distances ranging from 2.26–2.33 Å. There are six inequivalent O sites. In the first O site, O is bonded in a 5-coordinate geometry to four Na and one B atom. In the second O site, O is bonded in a 1-coordinate geometry to three Na, one B, and one Bi atom. In the third O site, O is bonded to three Na, one B, and one Bi atom to form distorted corner-sharing ONa3BiB trigonal bipyramids. In the fourth O site, O is bonded in a 1-coordinate geometry to two Na, one Si, and one Bi atom. In the fifth O site, O is bonded to two equivalent Na, one Si, and one Bi atom to form distorted corner-sharing ONa2SiBi tetrahedra. In the sixth O site, O is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na, one Si, and one Bi atom.

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2020-07-15. Materials Data on Na3SiBiBO7 by Materials Project. https://doi.org/10.17188/1301442

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