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DOE OSTI · 1282903

Materials Data on K2Bi3F11 by Materials Project

Abstract

K2Bi3F11 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to five F1- atoms to form distorted KF5 trigonal bipyramids that share corners with three equivalent KF7 hexagonal pyramids and corners with six equivalent KF5 trigonal bipyramids. There are a spread of K–F bond distances ranging from 2.47–2.77 Å. In the second K1+ site, K1+ is bonded to seven F1- atoms to form distorted KF7 hexagonal pyramids that share corners with three equivalent KF5 trigonal bipyramids and edges with six equivalent KF7 hexagonal pyramids. There are a spread of K–F bond distances ranging from 2.77–2.91 Å. There are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Bi–F bond distances ranging from 2.21–2.68 Å. In the second Bi3+ site, Bi3+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Bi–F bond distances ranging from 2.14–2.79 Å. In the third Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Bi–F bond distances ranging from 2.18–2.61 Å. There are eleven inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one K1+ and two equivalent Bi3+ atoms. In the second F1- site, F1- is bonded to three equivalent K1+ and one Bi3+ atom to form distorted FK3Bi tetrahedra that share corners with six equivalent FK3Bi tetrahedra and corners with three equivalent FK4 trigonal pyramids. In the third F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Bi3+ atoms. In the fourth F1- site, F1- is bonded to four K1+ atoms to form FK4 trigonal pyramids that share corners with three equivalent FK3Bi tetrahedra and corners with six equivalent FK4 trigonal pyramids. In the fifth F1- site, F1- is bonded in a 4-coordinate geometry to three equivalent K1+ and one Bi3+ atom. In the sixth F1- site, F1- is bonded in a 1-coordinate geometry to three Bi3+ atoms. In the seventh F1- site, F1- is bonded in a 1-coordinate geometry to one K1+ and two equivalent Bi3+ atoms. In the eighth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two Bi3+ atoms. In the ninth F1- site, F1- is bonded in a 1-coordinate geometry to three Bi3+ atoms. In the tenth F1- site, F1- is bonded in a bent 120 degrees geometry to two Bi3+ atoms. In the eleventh F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two equivalent Bi3+ atoms.

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2020-05-01. Materials Data on K2Bi3F11 by Materials Project. https://doi.org/10.17188/1282903

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