Materials Data on CeMg2 by Materials Project

Abstract

CeMg2 is alpha Samarium-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with six equivalent CeCe9Mg3 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one CeCe9Mg3 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.11–3.18 Å. In the second Mg site, Mg is bonded to nine Mg and three equivalent Ce atoms to form MgCe3Mg9 cuboctahedra that share corners with six equivalent CeCe9Mg3 cuboctahedra, corners with twelve MgCe3Mg9 cuboctahedra, edges with six equivalent CeCe9Mg3 cuboctahedra, edges with twelve MgMg12 cuboctahedra, faces with seven equivalent CeCe9Mg3 cuboctahedra, and faces with thirteen MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. All Mg–Ce bond lengths are 3.44 Å. In the third Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with six equivalent CeCe9Mg3 cuboctahedra, corners with twelve MgCe3Mg9 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one CeCe9Mg3 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are three shorter (3.11 Å) and six longer (3.18 Å) Mg–Mg bond lengths. Ce is bonded to three equivalent Mg and nine equivalent Ce atoms to form CeCe9Mg3 cuboctahedra that share corners with six equivalent CeCe9Mg3 cuboctahedra, corners with twelve MgMg12 cuboctahedra, edges with six equivalent MgCe3Mg9 cuboctahedra, edges with twelve equivalent CeCe9Mg3 cuboctahedra, faces with eight MgMg12 cuboctahedra, and faces with twelve equivalent CeCe9Mg3 cuboctahedra. There are six shorter (3.18 Å) and three longer (3.52 Å) Ce–Ce bond lengths.