Materials Data on AlSi5(CO6)2 by Materials Project

Abstract

(C)2AlSi5O12 is Keatite-derived structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional and consists of two ethyne molecules and one AlSi5O12 framework. In the AlSi5O12 framework, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. All Al–O bond lengths are 1.73 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.64 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.59–1.64 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. All Si–O bond lengths are 1.63 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms.