Materials Data on CaGeO3 by Materials Project

Abstract

CaGeO3 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.68 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.66 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form corner-sharing GeO4 tetrahedra. There are a spread of Ge–O bond distances ranging from 1.72–1.82 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form corner-sharing GeO4 tetrahedra. There is two shorter (1.72 Å) and two longer (1.82 Å) Ge–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Ge4+ atom. In the second O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form a mixture of distorted corner and edge-sharing OCa3Ge tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Ge4+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Ge4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two equivalent Ge4+ atoms.