Materials Data on Ce6Mg23C by Materials Project

Abstract

Mg23Ce6C crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded in a 1-coordinate geometry to ten Mg and three equivalent Ce atoms. There are a spread of Mg–Mg bond distances ranging from 2.98–3.45 Å. All Mg–Ce bond lengths are 3.78 Å. In the second Mg site, Mg is bonded to eight Mg and four equivalent Ce atoms to form MgCe4Mg8 cuboctahedra that share corners with twelve MgCe4Mg8 cuboctahedra, edges with two equivalent CCe6 octahedra, and faces with sixteen MgCe4Mg8 cuboctahedra. All Mg–Mg bond lengths are 2.93 Å. All Mg–Ce bond lengths are 3.73 Å. In the third Mg site, Mg is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. In the fourth Mg site, Mg is bonded to nine Mg and three equivalent Ce atoms to form MgCe3Mg9 cuboctahedra that share corners with twelve MgCe4Mg8 cuboctahedra, faces with twelve MgCe4Mg8 cuboctahedra, and a faceface with one CCe6 octahedra. All Mg–Mg bond lengths are 3.21 Å. All Mg–Ce bond lengths are 3.47 Å. Ce is bonded in a single-bond geometry to twelve Mg and one C atom. The Ce–C bond length is 2.57 Å. C is bonded to six equivalent Ce atoms to form CCe6 octahedra that share edges with twelve equivalent MgCe4Mg8 cuboctahedra and faces with eight equivalent MgCe3Mg9 cuboctahedra.