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DOE OSTI · 1733596

Materials Data on KTmF4 by Materials Project

Abstract

KTmF4 crystallizes in the trigonal P3_2 space group. The structure is three-dimensional. there are six inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 4-coordinate geometry to nine F1- atoms. There are a spread of K–F bond distances ranging from 2.61–3.29 Å. In the second K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one TmF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six TmF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.54–3.05 Å. In the third 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 2.58–3.05 Å. In the fourth K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one TmF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six TmF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.58–3.01 Å. In the fifth 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 2.58–2.93 Å. In the sixth K1+ site, K1+ is bonded to eight F1- atoms to form distorted KF8 hexagonal bipyramids that share a cornercorner with one TmF7 pentagonal bipyramid, edges with two KF8 hexagonal bipyramids, and edges with six TmF7 pentagonal bipyramids. There are a spread of K–F bond distances ranging from 2.60–3.05 Å. There are six inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.12–2.28 Å. In the second Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share corners with five TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.18–2.25 Å. In the third Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.12–2.27 Å. In the fourth Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share corners with five TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.18–2.25 Å. In the fifth Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share a cornercorner with one KF8 hexagonal bipyramid, corners with three equivalent TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.12–2.27 Å. In the sixth Tm3+ site, Tm3+ is bonded to seven F1- atoms to form TmF7 pentagonal bipyramids that share corners with five TmF7 pentagonal bipyramids, edges with three KF8 hexagonal bipyramids, and an edgeedge with one TmF7 pentagonal bipyramid. There are a spread of Tm–F bond distances ranging from 2.17–2.25 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 Tm3+ atoms. In the second F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Tm3+ atoms. In the third F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two equivalent Tm3+ atoms. In the fourth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Tm3+ atoms. In the fifth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Tm3+ atoms. In the sixth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Tm3+ atoms. In the seventh F1- site, F1- is bonded in a distorted linear geometry to one K1+ and two Tm3+ atoms. In the eighth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two equivalent Tm3+ atoms. In the ninth F1- site, F1- is bonded in a 2-coordinate geometry to two K1+ and two Tm3+ atoms. In the tenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the eleventh F1- site, F1- is bonded in a 3-coordinate geometry to one K1+ and two equivalent Tm3+ atoms. In the twelfth F1- site, F1- is bonded in a 2-coordinate geometry to one K1+ and two Tm3+ atoms. In the thirteenth F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of edge and corner-sharing FK3Tm tetrahedra. In the fourteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the fifteenth F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of distorted edge and corner-sharing FK3Tm tetrahedra. In the sixteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the seventeenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the eighteenth F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of distorted edge and corner-sharing FK3Tm tetrahedra. In the nineteenth F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the twentieth F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of distorted edge and corner-sharing FK3Tm tetrahedra. In the twenty-first F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of distorted edge and corner-sharing FK3Tm tetrahedra. In the twenty-second F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the twenty-third F1- site, F1- is bonded in a 4-coordinate geometry to two K1+ and two Tm3+ atoms. In the twenty-fourth F1- site, F1- is bonded to three K1+ and one Tm3+ atom to form a mixture of distorted edge and corner-sharing FK3Tm tetrahedra.

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2020-05-02. Materials Data on KTmF4 by Materials Project. https://doi.org/10.17188/1733596

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