Materials Data on Al2SiO6 by Materials Project
Al2SiO6 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with four equivalent SiO4 tetrahedra, and edges with two equivalent AlO6 octahedra. The corner-sharing octahedral tilt angles are 28°. There are a spread of Al–O bond distances ranging from 1.82–1.98 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with eight equivalent AlO6 octahedra. The corner-sharing octahedra tilt angles range from 49–51°. There are a spread of Si–O bond distances ranging from 1.65–1.68 Å. There are four inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two equivalent Al and one Si atom. In the second O site, O is bonded in a distorted trigonal planar geometry to two equivalent Al and one Si atom. In the third O site, O is bonded in a distorted trigonal planar geometry to two equivalent Al and one Si atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to two equivalent Al atoms.