Materials Data on CaScSi3HO9 by Materials Project

Abstract

CaScSi3HO9 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.60 Å. Sc3+ is bonded to six O2- atoms to form ScO6 octahedra that share corners with six SiO4 tetrahedra and an edgeedge with one ScO6 octahedra. There are a spread of Sc–O bond distances ranging from 2.05–2.31 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 ScO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three equivalent ScO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–62°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent ScO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–50°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.63 Å) H–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Sc3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Sc3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+, one Sc3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Si4+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sc3+, one Si4+, and one H1+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Sc3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms.