Materials Data on Al2Si2O11 by Materials Project

Abstract

(AlO3)2Si2O5 crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of one AlO3 sheet oriented in the (0, 0, 1) direction and one Si2O5 sheet oriented in the (0, 0, 1) direction. In the AlO3 sheet, Al is bonded to six O atoms to form distorted edge-sharing AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–1.89 Å. There are four inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the second O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the third O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the fourth O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the Si2O5 sheet, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. There are three 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 single-bond geometry to one Si atom.