DOI: 10.17188/1268749
title: Materials Data on Sr7Zr(Si2O7)3 by Materials Project

description: Sr7Zr(Si2O7)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.66 Å. In the second Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.67 Å. In the third Sr2+ site, Sr2+ is bonded to six O2- atoms to form SrO6 octahedra that share corners with six SiO4 tetrahedra. All Sr–O bond lengths are 2.56 Å. In the fourth Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.66 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra. All Zr–O bond lengths are 2.11 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SrO6 octahedra, a cornercorner with one ZrO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–54°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SrO6 octahedra, a cornercorner with one ZrO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–54°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SrO6 octahedra, a cornercorner with one ZrO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–54°. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one Si4+ atom. In the third O2- site, O2- is bonded to three Sr2+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OSr3Si tetrahedra. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one Zr4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one Zr4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Sr2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded to three Sr2+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OSr3Si tetrahedra. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Si4+ atom. In the ninth O2- site, O2- is bonded to three Sr2+ and one Si4+ atom to form a mixture of distorted edge and corner-sharing OSr3Si tetrahedra. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+, one Zr4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the twelfth O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms.