Materials Data on Cd2GeO4 by Materials Project

Abstract

Cd2GeO4 is Ilmenite-like structured and crystallizes in the orthorhombic Pnma 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 CdO6 octahedra, corners with four equivalent GeO4 tetrahedra, edges with two equivalent CdO6 octahedra, and an edgeedge with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–66°. There are a spread of Cd–O bond distances ranging from 2.29–2.47 Å. In the second Cd2+ site, Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with four equivalent CdO6 octahedra, corners with two equivalent GeO4 tetrahedra, edges with four CdO6 octahedra, and edges with two equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–66°. There are a spread of Cd–O bond distances ranging from 2.33–2.40 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with six CdO6 octahedra and edges with three CdO6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Ge–O bond distances ranging from 1.76–1.82 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Cd2+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cd2+ and one Ge4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Cd2+ and one Ge4+ atom.