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DOE OSTI · 1662834

Materials Data on KDy2F7 by Materials Project

Abstract

KDy2F7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of K–F bond distances ranging from 2.67–2.94 Å. In the second K1+ site, K1+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of K–F bond distances ranging from 2.68–2.77 Å. In the third K1+ site, K1+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of K–F bond distances ranging from 2.68–2.75 Å. In the fourth K1+ site, K1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of K–F bond distances ranging from 2.68–2.95 Å. There are five inequivalent Dy3+ sites. In the first Dy3+ site, Dy3+ is bonded in a body-centered cubic geometry to eight F1- atoms. There are a spread of Dy–F bond distances ranging from 2.22–2.45 Å. In the second Dy3+ site, Dy3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Dy–F bond distances ranging from 2.22–2.42 Å. In the third Dy3+ site, Dy3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Dy–F bond distances ranging from 2.22–2.38 Å. In the fourth Dy3+ site, Dy3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Dy–F bond distances ranging from 2.23–2.44 Å. In the fifth Dy3+ site, Dy3+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Dy–F bond distances ranging from 2.20–2.43 Å. There are nineteen inequivalent F1- sites. In the first F1- site, F1- is bonded to one K1+ and three Dy3+ atoms to form a mixture of distorted edge and corner-sharing FKDy3 tetrahedra. In the second F1- site, F1- is bonded to two K1+ and two Dy3+ atoms to form distorted FK2Dy2 tetrahedra that share corners with ten FK2Dy2 tetrahedra and edges with four FKDy3 tetrahedra. In the third F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one K1+ and two equivalent Dy3+ atoms. In the fourth F1- site, F1- is bonded to two K1+ and two equivalent Dy3+ atoms to form distorted FK2Dy2 tetrahedra that share corners with seven FKDy3 tetrahedra and edges with four FK2Dy2 tetrahedra. In the fifth F1- site, F1- is bonded to two K1+ and two equivalent Dy3+ atoms to form distorted FK2Dy2 tetrahedra that share corners with seven FKDy3 tetrahedra and edges with six FK2Dy2 tetrahedra. In the sixth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two Dy3+ atoms. In the seventh F1- site, F1- is bonded to two K1+ and two equivalent Dy3+ atoms to form distorted FK2Dy2 tetrahedra that share corners with seven FKDy3 tetrahedra and edges with four FK2Dy2 tetrahedra. In the eighth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two Dy3+ atoms. In the ninth F1- site, F1- is bonded to one K1+ and three Dy3+ atoms to form a mixture of distorted edge and corner-sharing FKDy3 tetrahedra. In the tenth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to two Dy3+ atoms. In the eleventh F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one K1+ and two equivalent Dy3+ atoms. In the twelfth F1- site, F1- is bonded in a 4-coordinate geometry to one K1+ and three Dy3+ atoms. In the thirteenth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Dy3+ atoms. In the fourteenth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Dy3+ atoms. In the fifteenth F1- site, F1- is bonded to one K1+ and three Dy3+ atoms to form FKDy3 tetrahedra that share corners with six FK2Dy2 tetrahedra and edges with three FKDy3 tetrahedra. In the sixteenth F1- site, F1- is bonded to two K1+ and two equivalent Dy3+ atoms to form a mixture of distorted edge and corner-sharing FK2Dy2 tetrahedra. In the seventeenth F1- site, F1- is bonded in a 4-coordinate geometry to one K1+ and three Dy3+ atoms. In the eighteenth F1- site, F1- is bonded to two K1+ and two Dy3+ atoms to form distorted FK2Dy2 tetrahedra that share corners with ten FKDy3 tetrahedra and edges with four FK2Dy2 tetrahedra. In the nineteenth F1- site, F1- is bonded to one K1+ and three Dy3+ atoms to form a mixture of distorted edge and corner-sharing FKDy3 tetrahedra.

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2020-04-29. Materials Data on KDy2F7 by Materials Project. https://doi.org/10.17188/1662834

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