DOI: 10.17188/1677846
title: Materials Data on Ce5(MgGe)8 by Materials Project

description: Ce5(MgGe)8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to four Ge atoms to form distorted MgGe4 tetrahedra that share corners with six CeGe6 octahedra, corners with six MgGe4 tetrahedra, edges with three CeGe6 octahedra, and edges with three MgGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–58°. There are a spread of Mg–Ge bond distances ranging from 2.76–2.97 Å. In the second Mg site, Mg is bonded to one Ce and four Ge atoms to form distorted MgCeGe4 tetrahedra that share corners with four CeGe6 octahedra, corners with six MgGe4 tetrahedra, edges with two equivalent CeGe6 octahedra, edges with three MgGe4 tetrahedra, and faces with three MgCe2Ge4 tetrahedra. The corner-sharing octahedra tilt angles range from 7–60°. The Mg–Ce bond length is 3.43 Å. There are a spread of Mg–Ge bond distances ranging from 2.65–2.89 Å. In the third Mg site, Mg is bonded to three equivalent Ce and four Ge atoms to form distorted MgCe3Ge4 tetrahedra that share a cornercorner with one CeGe6 octahedra, corners with five MgCeGe4 tetrahedra, edges with two equivalent CeGe6 octahedra, edges with six MgCeGe4 tetrahedra, and faces with four MgCe2Ge4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are two shorter (3.31 Å) and one longer (3.35 Å) Mg–Ce bond lengths. There are one shorter (2.72 Å) and three longer (2.75 Å) Mg–Ge bond lengths. In the fourth Mg site, Mg is bonded to two equivalent Ce and four Ge atoms to form distorted MgCe2Ge4 tetrahedra that share corners with three CeGe6 octahedra, corners with five MgGe4 tetrahedra, edges with three CeGe6 octahedra, edges with four MgCe3Ge4 tetrahedra, and faces with three MgCeGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–58°. Both Mg–Ce bond lengths are 3.36 Å. There are a spread of Mg–Ge bond distances ranging from 2.68–2.82 Å. There are three inequivalent Ce sites. In the first Ce site, Ce is bonded to six Ge atoms to form distorted CeGe6 octahedra that share corners with eight MgGe4 tetrahedra, edges with four CeGe6 octahedra, and edges with seven MgGe4 tetrahedra. There are a spread of Ce–Ge bond distances ranging from 3.06–3.26 Å. In the second Ce site, Ce is bonded in a 6-coordinate geometry to six Mg and six Ge atoms. There are a spread of Ce–Ge bond distances ranging from 3.15–3.29 Å. In the third Ce site, Ce is bonded to six Ge atoms to form distorted CeGe6 octahedra that share corners with twelve MgCe2Ge4 tetrahedra, edges with six CeGe6 octahedra, and edges with six MgCe2Ge4 tetrahedra. There are two shorter (3.04 Å) and four longer (3.12 Å) Ce–Ge bond lengths. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to two Mg, six Ce, and one Ge atom. The Ge–Ge bond length is 2.58 Å. In the second Ge site, Ge is bonded in a 7-coordinate geometry to four Mg and three Ce atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to six Mg and three Ce atoms. In the fourth Ge site, Ge is bonded in a 7-coordinate geometry to four Mg and three Ce atoms.