Materials Data on Sr5Al3F19 by Materials Project

Abstract

Sr5Al3F19 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Sr–F bond distances ranging from 2.36–2.71 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Sr–F bond distances ranging from 2.48–2.89 Å. In the third Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are four shorter (2.51 Å) and four longer (2.70 Å) Sr–F bond lengths. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of Al–F bond distances ranging from 1.81–1.84 Å. In the second Al3+ site, Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Al–F bond distances ranging from 1.79–1.83 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Al3+ atom. In the second F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Al3+ atom. In the third F1- site, F1- is bonded in a linear geometry to two equivalent Al3+ atoms. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to two Sr2+ and one Al3+ atom. In the fifth F1- site, F1- is bonded in a 4-coordinate geometry to four Sr2+ atoms. In the sixth F1- site, F1- is bonded in a linear geometry to two equivalent Al3+ atoms. In the seventh F1- site, F1- is bonded in a 1-coordinate geometry to three Sr2+ and one Al3+ atom. In the eighth F1- site, F1- is bonded in a 1-coordinate geometry to two Sr2+ and one Al3+ atom.