Materials Data on CaZr4O9 by Materials Project

Abstract

CaZr4O9 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted edge-sharing CaO6 octahedra. There are two shorter (2.29 Å) and four longer (2.34 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.17 Å) and two longer (2.31 Å) Ca–O bond lengths. There are four inequivalent Zr4+ sites. In the first 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 2.05–2.28 Å. In the second Zr4+ site, Zr4+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Zr–O bond distances ranging from 2.08–2.35 Å. In the third Zr4+ site, Zr4+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Zr–O bond distances ranging from 2.05–2.43 Å. In the fourth Zr4+ site, Zr4+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.06–2.53 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+ and three Zr4+ atoms to form distorted OCaZr3 tetrahedra that share corners with six OCaZr3 tetrahedra and edges with four OZr4 tetrahedra. In the second O2- site, O2- is bonded to three Ca2+ and one Zr4+ atom to form a mixture of corner and edge-sharing OCa3Zr tetrahedra. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Ca2+ and two equivalent Zr4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Zr4+ atoms. In the fifth O2- site, O2- is bonded to four Zr4+ atoms to form distorted OZr4 tetrahedra that share corners with four OCa3Zr tetrahedra and edges with four OZr4 tetrahedra. In the sixth O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of distorted corner and edge-sharing OZr4 tetrahedra. In the seventh O2- site, O2- is bonded to four Zr4+ atoms to form distorted OZr4 tetrahedra that share corners with four OCaZr3 tetrahedra and edges with four OZr4 tetrahedra. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to three Zr4+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to four Zr4+ atoms.