Materials Data on Sr10Al2ClF25 by Materials Project

Abstract

Sr10Al2F25Cl crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Sr–F bond distances ranging from 2.46–2.69 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to one Cl1- and eight F1- atoms. The Sr–Cl bond length is 3.23 Å. There are a spread of Sr–F bond distances ranging from 2.58–2.72 Å. Al3+ is bonded in an octahedral geometry to six equivalent F1- atoms. All Al–F bond lengths are 1.81 Å. Cl1- is bonded to six equivalent Sr2+ and twelve equivalent F1- atoms to form distorted ClSr6F12 octahedra that share corners with twelve equivalent FSr4Cl tetrahedra and edges with twelve equivalent FSr4Cl tetrahedra. All Cl–F bond lengths are 3.46 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to three Sr2+ and one Al3+ atom. In the second F1- site, F1- is bonded to four Sr2+ and one Cl1- atom to form distorted FSr4Cl tetrahedra that share a cornercorner with one ClSr6F12 octahedra, corners with eleven FSr4Cl tetrahedra, an edgeedge with one ClSr6F12 octahedra, edges with six equivalent FSr4Cl tetrahedra, and faces with two equivalent FSr4Cl tetrahedra. The corner-sharing octahedral tilt angles are 63°. In the third F1- site, F1- is bonded to four equivalent Sr2+ atoms to form corner-sharing FSr4 tetrahedra.