Materials Data on EuMg5 by Materials Project
Mg5Eu crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted q6 geometry to eight Mg and two equivalent Eu atoms. There are four shorter (3.04 Å) and four longer (3.11 Å) Mg–Mg bond lengths. Both Mg–Eu bond lengths are 3.72 Å. In the second Mg site, Mg is bonded to nine Mg and three equivalent Eu atoms to form distorted MgEu3Mg9 cuboctahedra that share corners with nine equivalent MgEu3Mg9 cuboctahedra, corners with nine equivalent EuMg12 cuboctahedra, edges with six equivalent MgEu3Mg9 cuboctahedra, faces with three equivalent EuMg12 cuboctahedra, and faces with five equivalent MgEu3Mg9 cuboctahedra. All Mg–Mg bond lengths are 3.45 Å. All Mg–Eu bond lengths are 3.45 Å. Eu is bonded to twelve Mg atoms to form EuMg12 cuboctahedra that share corners with eighteen equivalent MgEu3Mg9 cuboctahedra, edges with six equivalent EuMg12 cuboctahedra, faces with two equivalent EuMg12 cuboctahedra, and faces with six equivalent MgEu3Mg9 cuboctahedra.