Materials Data on Al3Si2H3O10 by Materials Project

Abstract

Al3Si2O7(OH)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with five SiO4 tetrahedra and edges with two AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–1.98 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with five SiO4 tetrahedra and edges with two AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–2.01 Å. In the third Al3+ site, Al3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Al–O bond distances ranging from 1.82–2.49 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–59°. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with five AlO6 octahedra. The corner-sharing octahedra tilt angles range from 48–58°. There is one shorter (1.65 Å) and three longer (1.66 Å) Si–O bond length. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.64 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (0.99 Å) and one longer (1.68 Å) H–O bond length. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Al3+ 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 distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one H1+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Al3+, one Si4+, and two H1+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Al3+, one Si4+, and one H1+ atom.