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DOE OSTI · 1276855

Materials Data on K2In(PSe4)2 by Materials Project

Abstract

K2In(PSe4)2 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se+1.88- atoms. There are a spread of K–Se bond distances ranging from 3.39–3.81 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se+1.88- atoms. There are a spread of K–Se bond distances ranging from 3.44–3.92 Å. In the third K1+ site, K1+ is bonded in a 9-coordinate geometry to eight Se+1.88- atoms. There are a spread of K–Se bond distances ranging from 3.47–3.90 Å. In the fourth K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Se+1.88- atoms. There are a spread of K–Se bond distances ranging from 3.50–3.74 Å. There are two inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to six Se+1.88- atoms to form InSe6 octahedra that share corners with two PSe4 tetrahedra and an edgeedge with one InSe6 octahedra. There are a spread of In–Se bond distances ranging from 2.77–2.86 Å. In the second In3+ site, In3+ is bonded to six Se+1.88- atoms to form InSe6 octahedra that share corners with two PSe4 tetrahedra and an edgeedge with one InSe6 octahedra. There are a spread of In–Se bond distances ranging from 2.79–2.90 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four Se+1.88- atoms to form PSe4 tetrahedra that share corners with two InSe6 octahedra. The corner-sharing octahedra tilt angles range from 76–78°. There are a spread of P–Se bond distances ranging from 2.19–2.30 Å. In the second P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se+1.88- atoms. There are a spread of P–Se bond distances ranging from 2.16–2.24 Å. In the third P5+ site, P5+ is bonded to four Se+1.88- atoms to form PSe4 tetrahedra that share corners with two InSe6 octahedra. The corner-sharing octahedra tilt angles range from 75–78°. There are a spread of P–Se bond distances ranging from 2.19–2.29 Å. In the fourth P5+ site, P5+ is bonded in a trigonal non-coplanar geometry to three Se+1.88- atoms. There are one shorter (2.15 Å) and two longer (2.24 Å) P–Se bond lengths. There are sixteen inequivalent Se+1.88- sites. In the first Se+1.88- site, Se+1.88- is bonded in a 2-coordinate geometry to two equivalent K1+, one In3+, and one P5+ atom. In the second Se+1.88- site, Se+1.88- is bonded in a 1-coordinate geometry to two K1+, one P5+, and one Se+1.88- atom. The Se–Se bond length is 2.37 Å. In the third Se+1.88- site, Se+1.88- is bonded in a 2-coordinate geometry to two K1+, one In3+, and one P5+ atom. In the fourth Se+1.88- site, Se+1.88- is bonded in a 1-coordinate geometry to two K1+, one P5+, and one Se+1.88- atom. The Se–Se bond length is 2.38 Å. In the fifth Se+1.88- site, Se+1.88- is bonded to two K1+, one In3+, and one P5+ atom to form distorted edge-sharing SeK2InP trigonal pyramids. In the sixth Se+1.88- site, Se+1.88- is bonded in a 2-coordinate geometry to one K1+, one In3+, and one P5+ atom. In the seventh Se+1.88- site, Se+1.88- is bonded in a 4-coordinate geometry to one K1+, two In3+, and one Se+1.88- atom. In the eighth Se+1.88- site, Se+1.88- is bonded in a 4-coordinate geometry to two K1+, one In3+, and one P5+ atom. In the ninth Se+1.88- site, Se+1.88- is bonded in a 4-coordinate geometry to one K1+, two In3+, and one Se+1.88- atom. In the tenth Se+1.88- site, Se+1.88- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the eleventh Se+1.88- site, Se+1.88- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the twelfth Se+1.88- site, Se+1.88- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the thirteenth Se+1.88- site, Se+1.88- is bonded in a 3-coordinate geometry to one K1+, one In3+, and one P5+ atom. In the fourteenth Se+1.88- site, Se+1.88- is bonded to two K1+, one In3+, and one P5+ atom to form distorted edge-sharing SeK2InP trigonal pyramids. In the fifteenth Se+1.88- site, Se+1.88- is bonded in a 1-coordinate geometry to three K1+ and one P5+ atom. In the sixteenth Se+1.88- site, Se+1.88- is bonded in a 2-coordinate geometry to one K1+, one In3+, and one P5+ atom.

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2020-07-15. Materials Data on K2In(PSe4)2 by Materials Project. https://doi.org/10.17188/1276855

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