Materials Data on Cs3Ge2Sb3O13 by Materials Project
Cs3Ge2Sb3O13 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.98 Å) and one longer (3.08 Å) Cs–O bond lengths. In the second Cs1+ site, Cs1+ is bonded to six O2- atoms to form distorted CsO6 pentagonal pyramids that share corners with six SbO6 octahedra and corners with six equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 61–62°. There are four shorter (3.39 Å) and two longer (3.41 Å) Cs–O bond lengths. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with three SbO6 octahedra, corners with three equivalent CsO6 pentagonal pyramids, and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 62–63°. There is one shorter (1.74 Å) and three longer (1.77 Å) Ge–O bond length. There are two inequivalent Sb5+ sites. In the first Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four equivalent SbO6 octahedra, corners with two equivalent CsO6 pentagonal pyramids, and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are four shorter (1.99 Å) and two longer (2.06 Å) Sb–O bond lengths. In the second Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four SbO6 octahedra, corners with two equivalent CsO6 pentagonal pyramids, and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–43°. There are a spread of Sb–O bond distances ranging from 1.99–2.05 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cs1+, one Ge4+, and one Sb5+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cs1+, one Ge4+, and one Sb5+ atom. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Ge4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Cs1+ and two equivalent Sb5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Cs1+ and two Sb5+ atoms.