Materials Data on BeAlSiHO5 by Materials Project

Abstract

BeAlSiHO5 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share corners with two equivalent AlO6 octahedra, corners with two equivalent BeO4 tetrahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Be–O bond distances ranging from 1.61–1.69 Å. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent BeO4 tetrahedra, corners with five equivalent SiO4 tetrahedra, and edges with two equivalent AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–2.00 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five equivalent AlO6 octahedra and corners with three equivalent BeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–56°. There are a spread of Si–O bond distances ranging from 1.64–1.66 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Be2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Al3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Be2+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Al3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Be2+, one Al3+, and one H1+ atom.