Materials Data on BaY6Si3B6(O12F)2 by Materials Project
BaY6(Si3B6O24)F2 crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.81 Å) and six longer (2.94 Å) Ba–O bond lengths. There are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 8-coordinate geometry to seven O2- and one F1- atom. There are a spread of Y–O bond distances ranging from 2.28–2.55 Å. The Y–F bond length is 2.41 Å. In the second Y3+ site, Y3+ is bonded in a 6-coordinate geometry to five O2- and one F1- atom. There are a spread of Y–O bond distances ranging from 2.29–2.34 Å. The Y–F bond length is 2.39 Å. B3+ is bonded to four O2- atoms to form BO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two equivalent BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.43–1.55 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent BO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Y3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Y3+, one B3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Y3+ and two equivalent B3+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Y3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Y3+, and two equivalent B3+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, two Y3+, and one B3+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Y3+ atoms. In the second F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Y3+ atoms.