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DOE OSTI · 1305431

Materials Data on Ba2Y5F19 by Materials Project

Abstract

Ba2Y5F19 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to four F1- atoms to form BaF4 trigonal pyramids that share corners with four YF6 octahedra. The corner-sharing octahedra tilt angles range from 14–41°. There are a spread of Ba–F bond distances ranging from 2.46–2.51 Å. In the second Ba2+ site, Ba2+ is bonded to four F1- atoms to form distorted BaF4 trigonal pyramids that share corners with four YF6 octahedra. The corner-sharing octahedra tilt angles range from 16–43°. There are a spread of Ba–F bond distances ranging from 2.46–2.53 Å. There are five inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to six F1- atoms to form YF6 octahedra that share corners with five YF6 octahedra and a cornercorner with one BaF4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 7–16°. There are a spread of Y–F bond distances ranging from 2.16–2.22 Å. In the second Y3+ site, Y3+ is bonded to six F1- atoms to form corner-sharing YF6 octahedra. The corner-sharing octahedra tilt angles range from 2–9°. There are a spread of Y–F bond distances ranging from 2.19–2.22 Å. In the third Y3+ site, Y3+ is bonded to six F1- atoms to form YF6 octahedra that share corners with three YF6 octahedra and corners with three BaF4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 9–12°. There are a spread of Y–F bond distances ranging from 2.19–2.23 Å. In the fourth Y3+ site, Y3+ is bonded to six F1- atoms to form YF6 octahedra that share corners with three equivalent YF6 octahedra and corners with three BaF4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 7–16°. There are a spread of Y–F bond distances ranging from 2.18–2.21 Å. In the fifth Y3+ site, Y3+ is bonded to six F1- atoms to form YF6 octahedra that share corners with five YF6 octahedra and a cornercorner with one BaF4 trigonal pyramid. The corner-sharing octahedra tilt angles range from 2–12°. There are a spread of Y–F bond distances ranging from 2.17–2.22 Å. There are nineteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to two equivalent Y3+ atoms. In the second F1- site, F1- is bonded in a linear geometry to one Ba2+ and one Y3+ atom. In the third F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the fourth F1- site, F1- is bonded in a bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the fifth F1- site, F1- is bonded in a linear geometry to two equivalent Y3+ atoms. In the sixth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the seventh F1- site, F1- is bonded in a bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the eighth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the ninth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the tenth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the eleventh F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the twelfth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the thirteenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the fourteenth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the fifteenth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the sixteenth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the seventeenth F1- site, F1- is bonded in a bent 150 degrees geometry to one Ba2+ and one Y3+ atom. In the eighteenth F1- site, F1- is bonded in a linear geometry to two Y3+ atoms. In the nineteenth F1- site, F1- is bonded in a distorted linear geometry to one Ba2+ and one Y3+ atom.

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2020-04-29. Materials Data on Ba2Y5F19 by Materials Project. https://doi.org/10.17188/1305431

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