Materials Data on CaVSi4H12O11 by Materials Project

Abstract

CaVSi4O11(H2)6 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of twenty-eight hydrogen molecules and one CaVSi4O11 framework. In the CaVSi4O11 framework, Ca2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.28 Å) and two longer (2.30 Å) Ca–O bond lengths. V2+ is bonded to five O2- atoms to form distorted VO5 trigonal bipyramids that share corners with four SiO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.63–2.04 Å. There are two inequivalent Si2+ sites. In the first Si2+ site, Si2+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent SiO4 tetrahedra and a cornercorner with one VO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si2+ site, Si2+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent SiO4 tetrahedra and a cornercorner with one VO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two Si2+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one V2+, and one Si2+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one V2+, and one Si2+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Si2+ atoms. In the fifth O2- site, O2- is bonded in a single-bond geometry to one V2+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si2+ atoms.