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DOE OSTI · 1748845

Materials Data on Ca14Al12Zn4O35 by Materials Project

Abstract

Ca14Zn4Al12O35 crystallizes in the cubic F23 space group. The structure is three-dimensional. there are three inequivalent Ca sites. In the first Ca site, Ca is bonded to seven O atoms to form distorted CaO7 pentagonal bipyramids that share a cornercorner with one AlO6 octahedra, corners with four equivalent CaO7 pentagonal bipyramids, corners with two equivalent ZnO4 tetrahedra, corners with four equivalent AlO4 tetrahedra, edges with two equivalent CaO6 pentagonal pyramids, and edges with three AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ca–O bond distances ranging from 2.28–2.69 Å. In the second Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are three shorter (2.32 Å) and three longer (2.43 Å) Ca–O bond lengths. In the third Ca site, Ca is bonded to six O atoms to form distorted CaO6 pentagonal pyramids that share corners with three equivalent CaO6 pentagonal pyramids, corners with six AlO4 tetrahedra, edges with three equivalent CaO7 pentagonal bipyramids, and a faceface with one AlO6 octahedra. There are three shorter (2.35 Å) and three longer (2.42 Å) Ca–O bond lengths. Zn is bonded to four O atoms to form ZnO4 tetrahedra that share corners with three equivalent CaO7 pentagonal bipyramids, corners with three equivalent ZnO4 tetrahedra, and corners with three equivalent AlO4 tetrahedra. There are one shorter (2.02 Å) and three longer (2.12 Å) Zn–O bond lengths. There are four inequivalent Al sites. In the first Al site, Al is bonded to four equivalent O atoms to form AlO4 tetrahedra that share corners with four equivalent AlO4 tetrahedra and edges with six equivalent CaO7 pentagonal bipyramids. All Al–O bond lengths are 1.78 Å. In the second Al site, Al is bonded to six equivalent O atoms to form AlO6 octahedra that share corners with six equivalent CaO7 pentagonal bipyramids and faces with four equivalent CaO6 pentagonal pyramids. All Al–O bond lengths are 1.95 Å. In the third Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with three equivalent CaO6 pentagonal pyramids, corners with four AlO4 tetrahedra, and edges with three equivalent CaO7 pentagonal bipyramids. There is three shorter (1.79 Å) and one longer (1.81 Å) Al–O bond length. In the fourth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four equivalent CaO7 pentagonal bipyramids, corners with two equivalent CaO6 pentagonal pyramids, corners with two equivalent ZnO4 tetrahedra, and corners with two equivalent AlO4 tetrahedra. There is two shorter (1.78 Å) and two longer (1.83 Å) Al–O bond length. There are five inequivalent O sites. In the first O site, O is bonded to two Ca, one Zn, and one Al atom to form distorted OCa2AlZn tetrahedra that share corners with two equivalent OCa5Al octahedra, corners with seven OCa2AlZn tetrahedra, corners with two equivalent OCa3Al2 trigonal bipyramids, corners with four equivalent OCa2Al2 trigonal pyramids, and an edgeedge with one OCa5Al octahedra. The corner-sharing octahedra tilt angles range from 34–70°. In the second O site, O is bonded to two Ca and two Al atoms to form distorted OCa2Al2 trigonal pyramids that share corners with two equivalent OCa5Al octahedra, corners with four equivalent OCa2AlZn tetrahedra, a cornercorner with one OCa3Al2 trigonal bipyramid, corners with six equivalent OCa2Al2 trigonal pyramids, an edgeedge with one OCa5Al octahedra, and an edgeedge with one OCa3Al2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 31–62°. In the third O site, O is bonded to four equivalent Zn atoms to form corner-sharing OZn4 tetrahedra. In the fourth O site, O is bonded to five Ca and one Al atom to form OCa5Al octahedra that share a cornercorner with one OCa5Al octahedra, corners with four equivalent OCa2AlZn tetrahedra, corners with two equivalent OCa3Al2 trigonal bipyramids, corners with four equivalent OCa2Al2 trigonal pyramids, edges with two equivalent OCa2AlZn tetrahedra, edges with two equivalent OCa2Al2 trigonal pyramids, and faces with four equivalent OCa5Al octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O site, O is bonded to three equivalent Ca and two Al atoms to form distorted OCa3Al2 trigonal bipyramids that share corners with three equivalent OCa5Al octahedra, corners with six equivalent OCa2AlZn tetrahedra, corners with three equivalent OCa2Al2 trigonal pyramids, edges with three equivalent OCa3Al2 trigonal bipyramids, and edges with three equivalent OCa2Al2 trigonal pyramids. The corner-sharing octahedral tilt angles are 33°.

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2020-04-29. Materials Data on Ca14Al12Zn4O35 by Materials Project. https://doi.org/10.17188/1748845

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