Materials Data on LiMg2 by Materials Project

Abstract

LiMg2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Li is bonded to six Mg atoms to form distorted LiMg6 cuboctahedra that share corners with six equivalent LiMg6 cuboctahedra, corners with eighteen MgMg12 cuboctahedra, edges with six equivalent LiMg6 cuboctahedra, edges with twelve MgLi3Mg9 cuboctahedra, a faceface with one LiMg6 cuboctahedra, and a faceface with one MgMg12 cuboctahedra. There are three shorter (3.06 Å) and three longer (3.11 Å) Li–Mg bond lengths. 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 MgMg12 cuboctahedra, corners with twelve equivalent LiMg6 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, faces with two equivalent LiMg6 cuboctahedra, and faces with eighteen MgMg12 cuboctahedra. There are six shorter (3.13 Å) and six longer (3.17 Å) Mg–Mg bond lengths. In the second Mg site, Mg is bonded to three equivalent Li and nine Mg atoms to form distorted MgLi3Mg9 cuboctahedra that share corners with six equivalent LiMg6 cuboctahedra, corners with eighteen MgLi3Mg9 cuboctahedra, edges with six equivalent LiMg6 cuboctahedra, edges with twelve MgMg12 cuboctahedra, and faces with fourteen MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.17 Å. In the third Mg site, Mg is bonded to six equivalent Li and six equivalent Mg atoms to form distorted MgLi6Mg6 cuboctahedra that share corners with twelve equivalent LiMg6 cuboctahedra, corners with eighteen MgLi3Mg9 cuboctahedra, edges with six equivalent MgLi6Mg6 cuboctahedra, edges with twelve equivalent LiMg6 cuboctahedra, and faces with eight MgLi3Mg9 cuboctahedra. All Mg–Mg bond lengths are 3.17 Å.