Materials Data on CaZrSi6O17 by Materials Project
CaZrSi6O17 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Ca is bonded to seven O atoms to form distorted CaO7 hexagonal pyramids that share corners with two SiO4 tetrahedra, edges with two equivalent ZrO6 octahedra, and edges with two SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.39–2.51 Å. Zr is bonded to six O atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent CaO7 hexagonal pyramids. There are a spread of Zr–O bond distances ranging from 2.03–2.22 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one CaO7 hexagonal pyramid. The corner-sharing octahedral tilt angles are 22°. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, corners with three SiO4 tetrahedra, and an edgeedge with one CaO7 hexagonal pyramid. The corner-sharing octahedral tilt angles are 23°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one CaO7 hexagonal pyramid, a cornercorner with one ZrO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Si–O bond distances ranging from 1.62–1.64 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one CaO7 hexagonal pyramid, a cornercorner with one ZrO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 25°. There are a spread of Si–O bond distances ranging from 1.62–1.64 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Si–O bond distances ranging from 1.61–1.64 Å. There are eighteen inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a 3-coordinate geometry to one Ca, one Zr, and one Si atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Zr, and one Si atom. In the seventh O site, O is bonded in a 3-coordinate geometry to one Ca, one Zr, and one Si atom. In the eighth O site, O is bonded in a 3-coordinate geometry to one Ca, one Zr, and one Si atom. In the ninth O site, O is bonded in a distorted T-shaped geometry to one Ca and two Si atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twelfth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the thirteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fourteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the sixteenth O site, O is bonded in a bent 150 degrees geometry to one Zr and one Si atom. In the seventeenth O site, O is bonded in a single-bond geometry to one Ca atom. In the eighteenth O site, O is bonded in a single-bond geometry to one Ca atom.