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DOE OSTI · 1655850

Materials Data on Ca2Zr5Ti2O16 by Materials Project

Abstract

Ca2Zr5Ti2O16 crystallizes in the orthorhombic Iba2 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.62 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.62 Å. There are five inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to seven O2- atoms to form ZrO7 pentagonal bipyramids that share corners with two TiO6 octahedra, a cornercorner with one ZrO7 pentagonal bipyramid, an edgeedge with one TiO6 octahedra, and edges with three ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 40–44°. There are a spread of Zr–O bond distances ranging from 2.09–2.23 Å. In the second Zr4+ site, Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with two equivalent TiO6 octahedra, a cornercorner with one ZrO7 pentagonal bipyramid, an edgeedge with one TiO6 octahedra, and edges with three ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 41–46°. There are a spread of Zr–O bond distances ranging from 2.10–2.30 Å. In the third Zr4+ site, Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with two TiO6 octahedra, a cornercorner with one ZrO7 pentagonal bipyramid, an edgeedge with one TiO6 octahedra, and edges with three ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 41–48°. There are a spread of Zr–O bond distances ranging from 2.12–2.28 Å. In the fourth Zr4+ site, Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with two equivalent TiO6 octahedra, a cornercorner with one ZrO7 pentagonal bipyramid, an edgeedge with one TiO6 octahedra, and edges with three ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 42–44°. There are a spread of Zr–O bond distances ranging from 2.11–2.23 Å. In the fifth Zr4+ site, Zr4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Zr–O bond distances ranging from 2.11–2.19 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 TiO6 octahedra, corners with four ZrO7 pentagonal bipyramids, and edges with two ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 41–45°. There are a spread of Ti–O bond distances ranging from 1.93–2.01 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two TiO6 octahedra, corners with four ZrO7 pentagonal bipyramids, and edges with two ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–41°. There are a spread of Ti–O bond distances ranging from 1.84–2.13 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Ti4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ca2+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded to one Ca2+ and three Zr4+ atoms to form distorted OCaZr3 tetrahedra that share corners with seven OCaZr3 tetrahedra and edges with four OZr3Ti tetrahedra. In the fifth O2- site, O2- is bonded to one Ca2+ and three Zr4+ atoms to form a mixture of distorted edge and corner-sharing OCaZr3 tetrahedra. In the sixth O2- site, O2- is bonded to one Ca2+ and three Zr4+ atoms to form OCaZr3 tetrahedra that share corners with seven OCaZr3 tetrahedra and edges with three OZr3Ti tetrahedra. In the seventh O2- site, O2- is bonded to one Ca2+ and three Zr4+ atoms to form distorted OCaZr3 tetrahedra that share corners with seven OZr3Ti tetrahedra and edges with four OCaZr3 tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Ti4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Ti4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Ti4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Ti4+ atom. In the twelfth O2- site, O2- is bonded to three Zr4+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OZr3Ti tetrahedra. In the thirteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Zr4+ and one Ti4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Zr4+ and one Ti4+ atom. In the fifteenth O2- site, O2- is bonded to three Zr4+ and one Ti4+ atom to form a mixture of distorted edge and corner-sharing OZr3Ti tetrahedra. In the sixteenth O2- site, O2- is bonded to two Ca2+ and two Zr4+ atoms to form OCa2Zr2 tetrahedra that share corners with eight OZr3Ti tetrahedra and edges with two OCaZr3 tetrahedra. In the seventeenth O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Zr4+ atoms to form a mixture of edge and corner-sharing OCa2Zr2 tetrahedra. In the eighteenth O2- site, O2- is bonded to two equivalent Ca2+ and two equivalent Zr4+ atoms to form OCa2Zr2 tetrahedra that share corners with eight OZr3Ti tetrahedra and edges with two equivalent OCaZr3 tetrahedra.

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2020-04-29. Materials Data on Ca2Zr5Ti2O16 by Materials Project. https://doi.org/10.17188/1655850

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