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DOE OSTI · 1263528

Materials Data on Ca4Ti3AlSi4O19F by Materials Project

Abstract

Ca4Ti3AlSi4O19F crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to six O2- and one F1- atom. There are a spread of Ca–O bond distances ranging from 2.37–2.63 Å. The Ca–F bond length is 2.31 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.63 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.27–2.62 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.27–2.62 Å. There are four 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 TiO6 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Ti–O bond distances ranging from 1.87–2.04 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Ti–O bond distances ranging from 1.86–2.05 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Ti–O bond distances ranging from 1.88–2.04 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent TiO6 octahedra and corners with four equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Ti–O bond distances ranging from 1.88–2.04 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- and two equivalent F1- atoms to form AlO4F2 octahedra that share corners with two equivalent AlO4F2 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. There is two shorter (1.88 Å) and two longer (1.94 Å) Al–O bond length. Both Al–F bond lengths are 1.87 Å. In the second Al3+ site, Al3+ is bonded to four O2- and two equivalent F1- atoms to form AlO4F2 octahedra that share corners with two equivalent AlO4F2 octahedra and corners with four equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. There is two shorter (1.90 Å) and two longer (1.93 Å) Al–O bond length. Both Al–F bond lengths are 1.87 Å. 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 TiO6 octahedra and corners with three AlO4F2 octahedra. The corner-sharing octahedra tilt angles range from 33–52°. There is one shorter (1.65 Å) and three longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4F2 octahedra and corners with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–54°. There is one shorter (1.64 Å) and three longer (1.65 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 38–53°. All Si–O bond lengths are 1.65 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 37–53°. All Si–O bond lengths are 1.65 Å. There are nineteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Ti4+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+ and two Ti4+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+ and two Ti4+ atoms. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Ti4+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Ti4+, and one Si4+ atom. F1- is bonded in a 3-coordinate geometry to one Ca2+ and two Al3+ atoms.

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2020-04-29. Materials Data on Ca4Ti3AlSi4O19F by Materials Project. https://doi.org/10.17188/1263528

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