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DOE OSTI · 1193025

Materials Data on Na5Ti2Si2PO13 by Materials Project

Abstract

Na5Ti2Si2PO13 is Esseneite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 4-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.28–3.04 Å. In the second Na1+ site, Na1+ is bonded to four O2- atoms to form distorted NaO4 tetrahedra that share a cornercorner with one NaO8 hexagonal bipyramid, corners with two SiO4 tetrahedra, corners with three equivalent PO4 tetrahedra, and an edgeedge with one NaO8 hexagonal bipyramid. There are a spread of Na–O bond distances ranging from 2.24–2.40 Å. In the third 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 2.25–2.78 Å. In the fourth 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 2.28–2.81 Å. In the fifth Na1+ site, Na1+ is bonded to eight O2- atoms to form distorted NaO8 hexagonal bipyramids that share corners with two equivalent NaO8 hexagonal bipyramids, corners with two equivalent TiO6 octahedra, a cornercorner with one NaO4 tetrahedra, a cornercorner with one PO4 tetrahedra, edges with two equivalent TiO6 octahedra, an edgeedge with one NaO4 tetrahedra, and edges with four SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–59°. There are a spread of Na–O bond distances ranging from 2.32–2.84 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent NaO8 hexagonal bipyramids, a cornercorner with one TiO6 octahedra, corners with three SiO4 tetrahedra, and edges with two equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 39°. There are a spread of Ti–O bond distances ranging from 1.84–2.27 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, a cornercorner with one PO4 tetrahedra, corners with four SiO4 tetrahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of Ti–O bond distances ranging from 1.90–2.09 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four TiO6 octahedra, a cornercorner with one NaO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 34–58°. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three TiO6 octahedra, a cornercorner with one NaO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with two equivalent NaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 13–50°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO8 hexagonal bipyramid, a cornercorner with one TiO6 octahedra, and corners with three equivalent NaO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. There is three shorter (1.55 Å) and one longer (1.59 Å) P–O bond length. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted tetrahedral geometry to three Na1+ and one P5+ atom. In the fourth O2- site, O2- is bonded to two Na1+ and two equivalent Ti4+ atoms to form distorted edge-sharing ONa2Ti2 tetrahedra. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Na1+ and two Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+, one Ti4+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to three Na1+, one Ti4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two equivalent Ti4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Ti4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two Si4+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Ti4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ti4+, and one Si4+ atom.

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2020-05-02. Materials Data on Na5Ti2Si2PO13 by Materials Project. https://doi.org/10.17188/1193025

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