Materials Data on CdGeO3 by Materials Project

Abstract

CdGeO3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with eight equivalent GeO4 tetrahedra and edges with three equivalent CdO6 octahedra. There are a spread of Cd–O bond distances ranging from 2.20–2.59 Å. In the second Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with six equivalent GeO4 tetrahedra and edges with five CdO6 octahedra. There are a spread of Cd–O bond distances ranging from 2.29–2.39 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with seven CdO6 octahedra and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–70°. There are a spread of Ge–O bond distances ranging from 1.74–1.83 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Cd2+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cd2+ and two equivalent Ge4+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Cd2+ and one Ge4+ atom.