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DOE OSTI · 1202152

Materials Data on Na8Ti5O14 by Materials Project

Abstract

Na8Ti5O14 is Krennerite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two NaO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 21–23°. There are a spread of Na–O bond distances ranging from 2.28–2.59 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two NaO6 octahedra, corners with two equivalent TiO6 octahedra, an edgeedge with one TiO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 14–25°. There are a spread of Na–O bond distances ranging from 2.37–2.63 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with two equivalent NaO6 octahedra, edges with two TiO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 14–18°. There are a spread of Na–O bond distances ranging from 2.29–2.61 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, edges with three TiO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 22–26°. There are a spread of Na–O bond distances ranging from 2.32–2.64 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two TiO6 octahedra, corners with four NaO6 octahedra, edges with two TiO6 octahedra, and edges with five NaO6 octahedra. The corner-sharing octahedra tilt angles range from 14–26°. There are a spread of Na–O bond distances ranging from 2.32–2.46 Å. In the sixth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two NaO6 octahedra, corners with three TiO6 octahedra, edges with two TiO6 octahedra, and edges with seven NaO6 octahedra. The corner-sharing octahedra tilt angles range from 1–23°. There are a spread of Na–O bond distances ranging from 2.37–2.53 Å. In the seventh Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.90 Å. In the eighth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.31–2.47 Å. In the ninth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent TiO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are a spread of Na–O bond distances ranging from 2.33–2.47 Å. There are five inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with three NaO6 octahedra, edges with three TiO6 octahedra, and edges with five NaO6 octahedra. The corner-sharing octahedra tilt angles range from 1–26°. There are a spread of Ti–O bond distances ranging from 1.81–2.30 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with three NaO6 octahedra, edges with four NaO6 octahedra, and edges with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 6–22°. There are a spread of Ti–O bond distances ranging from 1.84–2.17 Å. In the third Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.80–2.34 Å. In the fourth Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.77–2.39 Å. In the fifth Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with four NaO6 octahedra, edges with two TiO6 octahedra, and edges with four NaO6 octahedra. The corner-sharing octahedra tilt angles range from 6–26°. There are a spread of Ti–O bond distances ranging from 1.75–2.35 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to three Na1+ and two Ti4+ atoms to form distorted ONa3Ti2 trigonal bipyramids that share a cornercorner with one ONa5Ti octahedra, corners with three ONa2Ti3 square pyramids, a cornercorner with one ONa3Ti2 trigonal bipyramid, and edges with two OTi6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two Ti4+ atoms. In the third O2- site, O2- is bonded to five Na1+ and one Ti4+ atom to form distorted ONa5Ti octahedra that share corners with two OTi6 octahedra, corners with two ONa2Ti3 square pyramids, edges with two equivalent ONa5Ti octahedra, edges with two ONa2Ti3 square pyramids, and an edgeedge with one ONa3Ti2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 0–3°. In the fourth O2- site, O2- is bonded to two equivalent Na1+ and three Ti4+ atoms to form distorted ONa2Ti3 square pyramids that share corners with two ONa5Ti octahedra, a cornercorner with one ONa3Ti2 trigonal bipyramid, edges with four OTi6 octahedra, and an edgeedge with one ONa2Ti3 square pyramid. The corner-sharing octahedra tilt angles range from 8–78°. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to three Na1+ and three Ti4+ atoms. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Ti4+ atoms. In the seventh O2- site, O2- is bonded to six Ti4+ atoms to form OTi6 octahedra that share corners with two ONa5Ti octahedra, a cornercorner with one ONa4Ti square pyramid, an edgeedge with one OTi6 octahedra, edges with two equivalent ONa2Ti3 square pyramids, and an edgeedge with one ONa3Ti2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 3–6°. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two Ti4+ atoms. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to four Na1+ and two Ti4+ atoms. In the tenth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Ti4+ atoms. In the eleventh O2- site, O2- is bonded to four Na1+ and one Ti4+ atom to form distorted ONa4Ti square pyramids that share corners with two OTi6 octahedra, corners with two equivalent ONa3Ti2 trigonal bipyramids, an edgeedge with one ONa5Ti octahedra, and an edgeedge with one ONa4Ti square pyramid. The corner-sharing octahedra tilt angles range from 6–14°. In the twelfth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Ti4+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to four Na1+ and one Ti4+ atom. In the fourteenth O2- site, O2- is bonded to five Na1+ and one Ti4+ atom to form distorted ONa5Ti octahedra that share corners with two OTi6 octahedra, a cornercorner with one ONa2Ti3 square pyramid, a cornercorner with one ONa3Ti2 trigonal bipyramid, edges with two equivalent ONa5Ti octahedra, and an edgeedge with one ONa2Ti3 square pyramid. The corner-sharing octahedra tilt angles range from 0–6°.

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2020-04-30. Materials Data on Na8Ti5O14 by Materials Project. https://doi.org/10.17188/1202152

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