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DOE OSTI · 1267630

Materials Data on KNa9In2O8 by Materials Project

Abstract

KNa9In2O8 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.72–2.74 Å. There are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 square pyramids that share corners with two equivalent NaO4 tetrahedra, corners with three equivalent InO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with three equivalent NaO4 trigonal pyramids, an edgeedge with one InO4 tetrahedra, edges with two equivalent NaO4 tetrahedra, edges with two equivalent NaO5 trigonal bipyramids, and edges with two equivalent NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.37–2.61 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with three equivalent NaO5 square pyramids, corners with two equivalent NaO4 tetrahedra, corners with two equivalent InO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with four equivalent NaO4 trigonal pyramids, an edgeedge with one InO4 tetrahedra, and edges with two equivalent NaO5 trigonal bipyramids. There are a spread of Na–O bond distances ranging from 2.40–2.54 Å. In the third Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.68 Å. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent NaO4 tetrahedra, corners with four InO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with four NaO4 trigonal pyramids, an edgeedge with one NaO5 square pyramid, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Na–O bond distances ranging from 2.30–2.47 Å. In the fifth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share a cornercorner with one NaO5 square pyramid, corners with two equivalent NaO4 tetrahedra, corners with two InO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with three NaO4 trigonal pyramids, an edgeedge with one NaO5 square pyramid, an edgeedge with one NaO4 tetrahedra, an edgeedge with one InO4 tetrahedra, and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Na–O bond distances ranging from 2.26–2.41 Å. In the sixth Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 trigonal bipyramids that share a cornercorner with one NaO5 square pyramid, a cornercorner with one InO4 tetrahedra, corners with two equivalent NaO4 tetrahedra, corners with three equivalent NaO5 trigonal bipyramids, corners with three NaO4 trigonal pyramids, an edgeedge with one NaO5 square pyramid, an edgeedge with one NaO4 tetrahedra, edges with two equivalent InO4 tetrahedra, an edgeedge with one NaO5 trigonal bipyramid, and edges with two NaO4 trigonal pyramids. There are a spread of Na–O bond distances ranging from 2.44–2.56 Å. There are two inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to four O2- atoms to form InO4 tetrahedra that share corners with two equivalent NaO4 tetrahedra, corners with six NaO4 trigonal pyramids, an edgeedge with one NaO5 square pyramid, and edges with four equivalent NaO5 trigonal bipyramids. There are two shorter (2.09 Å) and two longer (2.11 Å) In–O bond lengths. In the second In3+ site, In3+ is bonded to four O2- atoms to form InO4 tetrahedra that share corners with three equivalent NaO5 square pyramids, corners with two equivalent NaO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, corners with four equivalent NaO4 trigonal pyramids, edges with two equivalent NaO4 tetrahedra, and an edgeedge with one NaO4 trigonal pyramid. There are a spread of In–O bond distances ranging from 2.09–2.16 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to six Na1+ and one In3+ atom to form distorted ONa6In pentagonal bipyramids that share corners with four ONa6In pentagonal bipyramids, corners with two equivalent OKNa3In trigonal bipyramids, edges with two equivalent ONa6In pentagonal bipyramids, and a faceface with one OKNa5In pentagonal bipyramid. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one In3+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to one K1+, four Na1+, and one In3+ atom. In the fourth O2- site, O2- is bonded to one K1+, five Na1+, and one In3+ atom to form distorted OKNa5In pentagonal bipyramids that share corners with two equivalent ONa6In pentagonal bipyramids, a cornercorner with one OKNa3In trigonal bipyramid, edges with three equivalent OKNa5In pentagonal bipyramids, an edgeedge with one OKNa3In trigonal bipyramid, and a faceface with one ONa6In pentagonal bipyramid. In the fifth O2- site, O2- is bonded in a 7-coordinate geometry to six Na1+ and one In3+ atom. In the sixth O2- site, O2- is bonded to one K1+, three Na1+, and one In3+ atom to form OKNa3In trigonal bipyramids that share corners with six ONa6In pentagonal bipyramids and edges with two equivalent OKNa5In pentagonal bipyramids.

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2020-05-02. Materials Data on KNa9In2O8 by Materials Project. https://doi.org/10.17188/1267630

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