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DOE OSTI · 1270800

Materials Data on Na5TiP2O9F by Materials Project

Abstract

Na5TiP2O9F crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five O2- and one F1- atom to form distorted NaO5F octahedra that share a cornercorner with one TiO5F octahedra, corners with two NaO6 octahedra, corners with four PO4 tetrahedra, a cornercorner with one NaO4F trigonal bipyramid, an edgeedge with one NaO4F trigonal bipyramid, a faceface with one NaO5F octahedra, and a faceface with one TiO5F octahedra. The corner-sharing octahedra tilt angles range from 45–79°. There are a spread of Na–O bond distances ranging from 2.27–2.57 Å. The Na–F bond length is 2.47 Å. In the second Na1+ site, Na1+ is bonded to four O2- and one F1- atom to form distorted NaO4F trigonal bipyramids that share a cornercorner with one TiO5F octahedra, corners with two NaO5F octahedra, corners with four PO4 tetrahedra, and edges with three NaO5F octahedra. The corner-sharing octahedra tilt angles range from 8–84°. There are a spread of Na–O bond distances ranging from 2.32–2.37 Å. The Na–F bond length is 2.41 Å. In the third Na1+ site, Na1+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.33–2.75 Å. The Na–F bond length is 2.38 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two equivalent NaO5F octahedra, corners with two equivalent TiO5F octahedra, corners with four PO4 tetrahedra, edges with two equivalent NaO5F octahedra, and edges with two equivalent NaO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 45–66°. There are a spread of Na–O bond distances ranging from 2.38–2.61 Å. In the fifth Na1+ site, Na1+ is bonded to five O2- and one F1- atom to form distorted NaO5F octahedra that share a cornercorner with one NaO5F octahedra, a cornercorner with one TiO5F octahedra, corners with four PO4 tetrahedra, a cornercorner with one NaO4F trigonal bipyramid, an edgeedge with one NaO6 octahedra, an edgeedge with one NaO4F trigonal bipyramid, a faceface with one NaO5F octahedra, and a faceface with one TiO5F octahedra. The corner-sharing octahedra tilt angles range from 70–79°. There are a spread of Na–O bond distances ranging from 2.32–2.62 Å. The Na–F bond length is 2.36 Å. In the sixth Na1+ site, Na1+ is bonded in a 6-coordinate geometry to four O2- and two equivalent F1- atoms. There are two shorter (2.42 Å) and two longer (2.66 Å) Na–O bond lengths. Both Na–F bond lengths are 2.29 Å. Ti4+ is bonded to five O2- and one F1- atom to form distorted TiO5F octahedra that share corners with three NaO5F octahedra, corners with four PO4 tetrahedra, a cornercorner with one NaO4F trigonal bipyramid, and faces with two NaO5F octahedra. The corner-sharing octahedra tilt angles range from 66–70°. There are a spread of Ti–O bond distances ranging from 1.72–2.06 Å. The Ti–F bond length is 2.26 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent TiO5F octahedra, corners with five NaO5F octahedra, and corners with two equivalent NaO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 39–67°. There are a spread of P–O bond distances ranging from 1.53–1.58 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent TiO5F octahedra, corners with five NaO5F octahedra, and corners with two equivalent NaO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 34–65°. There is two shorter (1.53 Å) and two longer (1.58 Å) P–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, 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 rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Na1+, one Ti4+, and one P5+ atom. In the fifth O2- site, O2- is bonded to three Na1+ and one P5+ atom to form distorted ONa3P tetrahedra that share corners with three equivalent FNa5Ti octahedra. The corner-sharing octahedra tilt angles range from 6–69°. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Ti4+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one Ti4+ atom. F1- is bonded to five Na1+ and one Ti4+ atom to form distorted FNa5Ti octahedra that share a cornercorner with one FNa5Ti octahedra and corners with three equivalent ONa3P tetrahedra. The corner-sharing octahedral tilt angles are 0°.

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2020-04-29. Materials Data on Na5TiP2O9F by Materials Project. https://doi.org/10.17188/1270800

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