Materials Data on SrAl4O7 by Materials Project

Abstract

SrAl4O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.84 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.83 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.81 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three Al3+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+ and two equivalent Al3+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Sr2+ and two equivalent Al3+ atoms.