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DOE OSTI · 1291493

Materials Data on Na6Ti11O24 by Materials Project

Abstract

Na6Ti11O24 is beta indium sulfide-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with twelve TiO6 octahedra. The corner-sharing octahedra tilt angles range from 60–65°. There are a spread of Na–O bond distances ranging from 2.15–2.18 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with eleven TiO6 octahedra. The corner-sharing octahedra tilt angles range from 57–72°. There are a spread of Na–O bond distances ranging from 2.17–2.25 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six NaO4 tetrahedra and edges with six TiO6 octahedra. There are two shorter (2.20 Å) and four longer (2.30 Å) Na–O bond lengths. In the fourth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with ten TiO6 octahedra. The corner-sharing octahedra tilt angles range from 52–72°. There are three shorter (2.16 Å) and one longer (2.18 Å) Na–O bond lengths. In the fifth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with ten TiO6 octahedra. The corner-sharing octahedra tilt angles range from 53–73°. There are three shorter (2.16 Å) and one longer (2.18 Å) Na–O bond lengths. In the sixth Na1+ site, Na1+ is bonded to four O2- atoms to form NaO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with eleven TiO6 octahedra. The corner-sharing octahedra tilt angles range from 58–72°. There are a spread of Na–O bond distances ranging from 2.18–2.23 Å. There are eight inequivalent Ti+3.82+ sites. In the first Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with five NaO4 tetrahedra and edges with six TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 2.00–2.05 Å. In the second Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent NaO4 tetrahedra and edges with six TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.98–2.06 Å. In the third Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six NaO4 tetrahedra, edges with two equivalent NaO6 octahedra, and edges with four TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.93–2.07 Å. In the fourth Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with five NaO4 tetrahedra and edges with six TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.98–2.08 Å. In the fifth Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with six NaO4 tetrahedra, an edgeedge with one NaO6 octahedra, and edges with five TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.83–2.18 Å. In the sixth Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six NaO4 tetrahedra, an edgeedge with one NaO6 octahedra, and edges with five TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.85–2.13 Å. In the seventh Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four NaO4 tetrahedra and edges with six TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.98–2.05 Å. In the eighth Ti+3.82+ site, Ti+3.82+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four NaO4 tetrahedra and edges with six TiO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.99–2.05 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form ONaTi3 tetrahedra that share corners with eight ONaTi3 tetrahedra, corners with four ONa2Ti2 trigonal pyramids, and edges with two equivalent ONaTi3 tetrahedra. In the second O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 tetrahedra that share corners with eight ONaTi3 tetrahedra, corners with four ONa2Ti2 trigonal pyramids, and edges with two ONaTi3 tetrahedra. In the third O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form a mixture of corner and edge-sharing ONaTi3 tetrahedra. In the fourth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form a mixture of corner and edge-sharing ONaTi3 tetrahedra. In the fifth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 tetrahedra that share corners with six ONaTi3 tetrahedra, corners with three ONa2Ti2 trigonal pyramids, and edges with three ONaTi3 tetrahedra. In the sixth O2- site, O2- is bonded to two Na1+ and two Ti+3.82+ atoms to form distorted ONa2Ti2 trigonal pyramids that share corners with four ONaTi3 tetrahedra, corners with eight ONa2Ti2 trigonal pyramids, an edgeedge with one ONa2Ti2 tetrahedra, and edges with two ONa2Ti2 trigonal pyramids. In the seventh O2- site, O2- is bonded to two Na1+ and two Ti+3.82+ atoms to form distorted ONa2Ti2 trigonal pyramids that share corners with six ONaTi3 tetrahedra, corners with six ONa2Ti2 trigonal pyramids, and edges with three ONa2Ti2 trigonal pyramids. In the eighth O2- site, O2- is bonded to two Na1+ and two equivalent Ti+3.82+ atoms to form distorted ONa2Ti2 trigonal pyramids that share corners with six ONaTi3 tetrahedra, corners with six ONa2Ti2 trigonal pyramids, and edges with three ONa2Ti2 trigonal pyramids. In the ninth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Ti+3.82+ atoms. In the tenth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 trigonal pyramids that share corners with six ONaTi3 tetrahedra, corners with six ONa2Ti2 trigonal pyramids, and edges with three ONa2Ti2 trigonal pyramids. In the eleventh O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 tetrahedra that share corners with five ONaTi3 tetrahedra, corners with three ONa2Ti2 trigonal pyramids, and edges with three ONaTi3 tetrahedra. In the twelfth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form ONaTi3 tetrahedra that share corners with five ONaTi3 tetrahedra, corners with three ONa2Ti2 trigonal pyramids, and edges with three ONaTi3 tetrahedra. In the thirteenth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 trigonal pyramids that share corners with four ONaTi3 tetrahedra, corners with eight ONa2Ti2 trigonal pyramids, an edgeedge with one ONa2Ti2 tetrahedra, and edges with two equivalent ONa2Ti2 trigonal pyramids. In the fourteenth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form a mixture of corner and edge-sharing ONaTi3 tetrahedra. In the fifteenth O2- site, O2- is bonded to two Na1+ and two equivalent Ti+3.82+ atoms to form distorted ONa2Ti2 tetrahedra that share corners with three ONaTi3 tetrahedra, corners with nine ONa2Ti2 trigonal pyramids, and edges with three ONa2Ti2 trigonal pyramids. In the sixteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Ti+3.82+ atoms. In the seventeenth O2- site, O2- is bonded to one Na1+ and three Ti+3.82+ atoms to form distorted ONaTi3 tetrahedra that share corners with nine ONaTi3 tetrahedra and corners with three ONa2Ti2 trigonal pyramids. In the eighteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three Ti+3.82+ atoms.

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2020-04-30. Materials Data on Na6Ti11O24 by Materials Project. https://doi.org/10.17188/1291493

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