Materials Data on LiMg2 by Materials Project

Abstract

LiMg2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Li is bonded to two equivalent Li and ten Mg atoms to form distorted LiLi2Mg10 cuboctahedra that share corners with six equivalent LiLi2Mg10 cuboctahedra, corners with twelve MgLi4Mg8 cuboctahedra, edges with eight equivalent LiLi2Mg10 cuboctahedra, edges with ten MgLi4Mg8 cuboctahedra, faces with six equivalent LiLi2Mg10 cuboctahedra, and faces with fourteen MgLi4Mg8 cuboctahedra. Both Li–Li bond lengths are 3.14 Å. There are a spread of Li–Mg bond distances ranging from 3.11–3.14 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded to four equivalent Li and eight Mg atoms to form MgLi4Mg8 cuboctahedra that share corners with six equivalent LiLi2Mg10 cuboctahedra, corners with twelve MgLi4Mg8 cuboctahedra, edges with three equivalent LiLi2Mg10 cuboctahedra, edges with fifteen MgLi4Mg8 cuboctahedra, faces with eight equivalent LiLi2Mg10 cuboctahedra, and faces with twelve MgLi4Mg8 cuboctahedra. There are four shorter (3.11 Å) and four longer (3.14 Å) Mg–Mg bond lengths. In the second Mg site, Mg is bonded to six equivalent Li and six Mg atoms to form MgLi6Mg6 cuboctahedra that share corners with six equivalent LiLi2Mg10 cuboctahedra, corners with twelve MgLi4Mg8 cuboctahedra, edges with seven equivalent LiLi2Mg10 cuboctahedra, edges with eleven equivalent MgLi4Mg8 cuboctahedra, faces with six equivalent LiLi2Mg10 cuboctahedra, and faces with fourteen MgLi4Mg8 cuboctahedra. There are two shorter (3.11 Å) and two longer (3.14 Å) Mg–Mg bond lengths.