Materials Data on Be6Al4Si12O37 by Materials Project

Abstract

(Be3Al2Si6O18)4O2 crystallizes in the hexagonal P622 space group. The structure is three-dimensional and consists of one water molecule and one Be3Al2Si6O18 framework. In the Be3Al2Si6O18 framework, Be is bonded to four equivalent O atoms to form distorted BeO4 trigonal pyramids that share corners with four equivalent SiO4 tetrahedra and edges with two equivalent AlO6 octahedra. All Be–O bond lengths are 1.67 Å. Al is bonded to six equivalent O atoms to form AlO6 octahedra that share corners with six equivalent SiO4 tetrahedra and edges with three equivalent BeO4 trigonal pyramids. All Al–O bond lengths are 1.93 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent AlO6 octahedra, corners with two equivalent SiO4 tetrahedra, and corners with two equivalent BeO4 trigonal pyramids. The corner-sharing octahedral tilt angles are 44°. There is two shorter (1.61 Å) and two longer (1.64 Å) Si–O bond length. There are two inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Be, one Al, and one Si atom. In the second O site, O is bonded in a linear geometry to two equivalent Si atoms.