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DOE OSTI · 1720551

Materials Data on CaZrTi2O7 by Materials Project

Abstract

CaZrTi2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.41–2.54 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 2.40–2.60 Å. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with three TiO6 octahedra, a cornercorner with one TiO5 trigonal bipyramid, edges with two TiO6 octahedra, and edges with two equivalent ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 43–47°. There are a spread of Zr–O bond distances ranging from 2.05–2.39 Å. In the second Zr4+ site, Zr4+ is bonded to seven O2- atoms to form distorted ZrO7 pentagonal bipyramids that share corners with three TiO6 octahedra, a cornercorner with one TiO5 trigonal bipyramid, edges with two TiO6 octahedra, and edges with two equivalent ZrO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 44–49°. There are a spread of Zr–O bond distances ranging from 2.10–2.38 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 four TiO6 octahedra, corners with two ZrO7 pentagonal bipyramids, corners with two equivalent TiO5 trigonal bipyramids, and an edgeedge with one ZrO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–54°. There are a spread of Ti–O bond distances ranging from 1.89–2.13 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four TiO6 octahedra, corners with two ZrO7 pentagonal bipyramids, an edgeedge with one ZrO7 pentagonal bipyramid, and an edgeedge with one TiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 34–54°. There are a spread of Ti–O bond distances ranging from 1.85–2.11 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four TiO6 octahedra, corners with two ZrO7 pentagonal bipyramids, edges with two ZrO7 pentagonal bipyramids, and an edgeedge with one TiO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Ti–O bond distances ranging from 1.92–2.02 Å. In the fourth Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with two equivalent TiO6 octahedra, corners with two ZrO7 pentagonal bipyramids, and edges with two TiO6 octahedra. The corner-sharing octahedra tilt angles range from 51–53°. There are a spread of Ti–O bond distances ranging from 1.82–2.19 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+ and three Ti4+ atoms to form distorted OCaTi3 trigonal pyramids that share corners with three OCa2ZrTi tetrahedra, corners with three equivalent OCaTi3 trigonal pyramids, and edges with two OCa2ZrTi tetrahedra. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Zr4+, and one Ti4+ atom. In the fourth O2- site, O2- is bonded to two equivalent Ca2+, one Zr4+, and one Ti4+ atom to form distorted OCa2ZrTi tetrahedra that share corners with five equivalent OCa2ZrTi tetrahedra, corners with two OCaTi3 trigonal pyramids, an edgeedge with one OCa2ZrTi tetrahedra, and edges with two OCaTi3 trigonal pyramids. In the fifth O2- site, O2- is bonded to two equivalent Ca2+, one Zr4+, and one Ti4+ atom to form distorted OCa2ZrTi tetrahedra that share corners with five equivalent OCa2ZrTi tetrahedra, corners with two OCaTi3 trigonal pyramids, an edgeedge with one OCa2ZrTi tetrahedra, and edges with two OCaTi3 trigonal pyramids. In the sixth O2- site, O2- is bonded to two equivalent Ca2+, one Zr4+, and one Ti4+ atom to form distorted OCa2ZrTi tetrahedra that share a cornercorner with one OCaTi3 trigonal pyramid and an edgeedge with one OCa2ZrTi tetrahedra. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Zr4+ and two Ti4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Zr4+ and two Ti4+ atoms. In the ninth O2- site, O2- is bonded to one Ca2+ and three Ti4+ atoms to form distorted OCaTi3 trigonal pyramids that share corners with two OCa2ZrTi tetrahedra, corners with three equivalent OCaTi3 trigonal pyramids, and edges with two OCa2ZrTi tetrahedra. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+ and three Ti4+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Zr4+, and one Ti4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Zr4+, and one Ti4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Zr4+, and one Ti4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Zr4+, and one Ti4+ atom.

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2020-04-30. Materials Data on CaZrTi2O7 by Materials Project. https://doi.org/10.17188/1720551

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