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DOE OSTI · 1751196

Materials Data on Na5Ca7Zr2TiMnSi8(O8F)4 by Materials Project

Abstract

Na5Ca7Zr2TiMnSi8(O8F)4 is Esseneite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to seven O2- and one F1- atom. There are a spread of Na–O bond distances ranging from 2.34–2.84 Å. The Na–F bond length is 2.33 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to four O2- and two F1- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.62 Å. There are one shorter (2.38 Å) and one longer (2.42 Å) Na–F bond lengths. In the third Na1+ site, Na1+ is bonded to six O2- and two equivalent F1- atoms to form distorted NaO6F2 hexagonal bipyramids that share corners with two equivalent CaO5F octahedra, edges with two equivalent CaO4F2 octahedra, edges with two equivalent TiO6 octahedra, and edges with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Na–O bond distances ranging from 2.57–2.69 Å. Both Na–F bond lengths are 2.25 Å. There are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to five O2- and one F1- atom to form distorted CaO5F octahedra that share a cornercorner with one NaO6F2 hexagonal bipyramid, a cornercorner with one CaO4F2 octahedra, corners with five SiO4 tetrahedra, an edgeedge with one ZrO6 octahedra, and edges with two equivalent CaO6 octahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Ca–O bond distances ranging from 2.33–2.61 Å. The Ca–F bond length is 2.28 Å. In the second Ca2+ site, Ca2+ is bonded to four O2- and two F1- atoms to form distorted CaO4F2 octahedra that share a cornercorner with one ZrO6 octahedra, corners with two CaO5F octahedra, corners with two SiO4 tetrahedra, an edgeedge with one NaO6F2 hexagonal bipyramid, an edgeedge with one CaO6F2 hexagonal bipyramid, an edgeedge with one TiO6 octahedra, and an edgeedge with one MnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–68°. There are a spread of Ca–O bond distances ranging from 2.27–2.45 Å. There are one shorter (2.29 Å) and one longer (2.33 Å) Ca–F bond lengths. In the third Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO4F2 octahedra, a cornercorner with one TiO6 octahedra, corners with five SiO4 tetrahedra, an edgeedge with one ZrO6 octahedra, and edges with two equivalent CaO5F octahedra. The corner-sharing octahedra tilt angles range from 52–65°. There are a spread of Ca–O bond distances ranging from 2.32–2.49 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- and two equivalent F1- atoms to form distorted CaO6F2 hexagonal bipyramids that share edges with two equivalent CaO4F2 octahedra, edges with two equivalent MnO6 octahedra, and edges with four SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.40–2.61 Å. Both Ca–F bond lengths are 2.22 Å. Zr3+ is bonded to six O2- atoms to form ZrO6 octahedra that share a cornercorner with one CaO4F2 octahedra, a cornercorner with one MnO6 octahedra, corners with five SiO4 tetrahedra, and edges with two CaO6 octahedra. The corner-sharing octahedra tilt angles range from 43–68°. There are a spread of Zr–O bond distances ranging from 2.06–2.25 Å. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four SiO4 tetrahedra, edges with two equivalent NaO6F2 hexagonal bipyramids, and edges with two equivalent CaO4F2 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ti–O bond distances ranging from 1.91–2.03 Å. Mn7+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent ZrO6 octahedra, corners with four SiO4 tetrahedra, edges with two equivalent CaO6F2 hexagonal bipyramids, and edges with two equivalent CaO4F2 octahedra. The corner-sharing octahedral tilt angles are 43°. There is four shorter (1.95 Å) and two longer (1.97 Å) Mn–O bond length. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, a cornercorner with one MnO6 octahedra, corners with four CaO5F octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one CaO6F2 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 40–68°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, a cornercorner with one MnO6 octahedra, corners with three CaO5F octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one CaO6F2 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 40–63°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TiO6 octahedra, corners with two equivalent ZrO6 octahedra, corners with three CaO5F octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one NaO6F2 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 30–76°. There is one shorter (1.63 Å) and three longer (1.64 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, a cornercorner with one TiO6 octahedra, corners with two CaO5F octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one NaO6F2 hexagonal bipyramid. The corner-sharing octahedra tilt angles range from 31–69°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Zr3+, and one Si4+ atom. In the second O2- site, O2- is bonded to one Na1+, two Ca2+, and one Si4+ atom to form distorted ONaCa2Si tetrahedra that share a cornercorner with one ONaCa2Ti tetrahedra and corners with two FNa2Ca2 tetrahedra. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Zr3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Zr3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Zr3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Ti4+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Mn7+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Zr3+, and one Mn7+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Ca2+, and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ca2+, one Zr3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mn7+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded to one Na1+, two Ca2+, and one Ti4+ atom to form distorted ONaCa2Ti tetrahedra that share corners with two ONaCa2Si tetrahedra and corners with four FNa2Ca2 tetrahedra. In the sixteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Na1+ and two Si4+ atoms. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to two Na1+ and two Ca2+ atoms to form distorted FNa2Ca2 tetrahedra that share a cornercorner with one FNa2Ca2 tetrahedra, corners with three ONaCa2Ti tetrahedra, and an edgeedge with one FNa2Ca2 tetrahedra. In the second F1- site, F1- is bonded to two Na1+ and two Ca2+ atoms to form FNa2Ca2 tetrahedra that share a cornercorner with one FNa2Ca2 tetrahedra, corners with three ONaCa2Si tetrahedra, and an edgeedge with one FNa2Ca2 tetrahedra.

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2020-04-29. Materials Data on Na5Ca7Zr2TiMnSi8(O8F)4 by Materials Project. https://doi.org/10.17188/1751196

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