Materials Data on CsBe4Al4(B3O7)4 by Materials Project

Abstract

CsBe4Al4(B3O7)4 crystallizes in the cubic P-43m space group. The structure is three-dimensional. Cs is bonded in a 12-coordinate geometry to twelve equivalent O atoms. All Cs–O bond lengths are 3.32 Å. Be is bonded to four O atoms to form BeO4 tetrahedra that share corners with three equivalent AlO6 octahedra and corners with six equivalent BO4 tetrahedra. The corner-sharing octahedral tilt angles are 61°. There is one shorter (1.56 Å) and three longer (1.67 Å) Be–O bond length. Al is bonded to six O atoms to form AlO6 octahedra that share corners with three equivalent BeO4 tetrahedra, corners with six equivalent BO4 tetrahedra, and edges with three equivalent AlO6 octahedra. There is three shorter (1.93 Å) and three longer (1.97 Å) Al–O bond length. B is bonded to four O atoms to form BO4 tetrahedra that share corners with two equivalent AlO6 octahedra, corners with two equivalent BeO4 tetrahedra, and corners with four equivalent BO4 tetrahedra. The corner-sharing octahedral tilt angles are 62°. All B–O bond lengths are 1.50 Å. There are three inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to one Cs, one Be, and two equivalent B atoms. In the second O site, O is bonded to one Be and three equivalent Al atoms to form distorted edge-sharing OBeAl3 tetrahedra. In the third O site, O is bonded in a trigonal planar geometry to one Al and two equivalent B atoms.