Materials Data on K2Al2Si3(HO5)2 by Materials Project

Abstract

K2Al2Si3O10H2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional and consists of sixteen hydrogen molecules and one K2Al2Si3O10 framework. In the K2Al2Si3O10 framework, K1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of K–O bond distances ranging from 2.80–2.89 Å. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.77 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 two equivalent AlO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There is two shorter (1.63 Å) and two longer (1.65 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with three equivalent AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two Si4+ atoms.