Materials Data on Al(SiO3)2 by Materials Project

Abstract

Al(SiO3)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two Al(SiO3)2 sheets oriented in the (0, 0, 1) direction. Al is bonded to six O atoms to form AlO6 octahedra that share corners with four SiO4 tetrahedra and edges with three equivalent AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.89–1.94 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent AlO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–55°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent AlO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are six inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two equivalent Al atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a trigonal planar geometry to two equivalent Al and one Si atom. In the sixth O site, O is bonded in a trigonal planar geometry to two equivalent Al and one Si atom.