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DOE OSTI · 1653070

Materials Data on KHoF4 by Materials Project

Abstract

KHoF4 crystallizes in the trigonal P3_1 space group. The structure is three-dimensional. there are six inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one HoF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six HoF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.55–3.08 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of K–F bond distances ranging from 2.61–3.01 Å. In the third K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one HoF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six HoF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.61–3.03 Å. In the fourth K1+ site, K1+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of K–F bond distances ranging from 2.59–3.06 Å. In the fifth K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one HoF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six HoF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.62–3.09 Å. In the sixth K1+ site, K1+ is bonded in a distorted body-centered cubic geometry to eight F1- atoms. There are a spread of K–F bond distances ranging from 2.60–2.90 Å. There are six inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.16–2.30 Å. In the second Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share corners with five HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.21–2.28 Å. In the third Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.16–2.29 Å. In the fourth Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share corners with five HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.21–2.28 Å. In the fifth Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.16–2.29 Å. In the sixth Ho3+ site, Ho3+ is bonded to seven F1- atoms to form HoF7 pentagonal bipyramids that share corners with five HoF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one HoF7 pentagonal bipyramid. There are a spread of Ho–F bond distances ranging from 2.21–2.28 Å. There are twenty-four inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the second F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Ho3+ atoms. In the third F1- site, F1- is bonded in a 3-coordinate geometry to one K1+ and two equivalent Ho3+ atoms. In the fourth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Ho3+ atoms. In the fifth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the sixth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Ho3+ atoms. In the seventh F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Ho3+ atoms. In the eighth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two equivalent Ho3+ atoms. In the ninth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Ho3+ atoms. In the tenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the eleventh F1- site, F1- is bonded in a 3-coordinate geometry to one K1+ and two equivalent Ho3+ atoms. In the twelfth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Ho3+ atoms. In the thirteenth F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of corner and edge-sharing FK3Ho tetrahedra. In the fourteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the fifteenth F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of distorted corner and edge-sharing FK3Ho tetrahedra. In the sixteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the seventeenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the eighteenth F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of distorted corner and edge-sharing FK3Ho tetrahedra. In the nineteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the twentieth F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of distorted corner and edge-sharing FK3Ho tetrahedra. In the twenty-first F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of distorted corner and edge-sharing FK3Ho tetrahedra. In the twenty-second F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the twenty-third F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Ho3+ atoms. In the twenty-fourth F1- site, F1- is bonded to three K1+ and one Ho3+ atom to form a mixture of distorted corner and edge-sharing FK3Ho tetrahedra.

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2020-04-29. Materials Data on KHoF4 by Materials Project. https://doi.org/10.17188/1653070

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