Materials Data on SrYb4Si5O17 by Materials Project
SrYb4(Si2O7)(Si3O10) crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.54–2.66 Å. There are two inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded to six O2- atoms to form distorted YbO6 pentagonal pyramids that share corners with six SiO4 tetrahedra, an edgeedge with one YbO6 octahedra, and edges with two equivalent YbO6 pentagonal pyramids. There are a spread of Yb–O bond distances ranging from 2.30–2.38 Å. In the second Yb3+ site, Yb3+ is bonded to six O2- atoms to form distorted YbO6 octahedra that share corners with six SiO4 tetrahedra, an edgeedge with one YbO6 octahedra, and an edgeedge with one YbO6 pentagonal pyramid. There are a spread of Yb–O bond distances ranging from 2.29–2.37 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 corners with four equivalent YbO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent YbO6 octahedra, corners with three equivalent YbO6 pentagonal pyramids, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–50°. There are a spread of Si–O bond distances ranging from 1.62–1.68 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent YbO6 octahedra, corners with three equivalent YbO6 pentagonal pyramids, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Yb3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Yb3+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, one Yb3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Yb3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Yb3+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Sr2+, two equivalent Yb3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Sr2+, two equivalent Yb3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+, one Yb3+, and one Si4+ atom.