Materials Data on LiMg by Materials Project

Abstract

LiMg crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Li sites. In the first Li site, Li is bonded to six Li and six Mg atoms to form distorted LiLi6Mg6 cuboctahedra that share corners with six equivalent MgLi4Mg8 cuboctahedra, corners with twelve LiLi6Mg6 cuboctahedra, edges with three equivalent LiLi8Mg4 cuboctahedra, edges with fifteen MgLi4Mg8 cuboctahedra, faces with six LiLi6Mg6 cuboctahedra, and faces with eight MgLi4Mg8 cuboctahedra. There are four shorter (3.09 Å) and two longer (3.20 Å) Li–Li bond lengths. There are four shorter (3.08 Å) and two longer (3.09 Å) Li–Mg bond lengths. In the second Li site, Li is bonded to eight Li and four Mg atoms to form distorted LiLi8Mg4 cuboctahedra that share corners with six equivalent MgLi4Mg8 cuboctahedra, corners with twelve LiLi6Mg6 cuboctahedra, edges with three equivalent LiLi6Mg6 cuboctahedra, edges with eleven MgLi4Mg8 cuboctahedra, faces with six LiLi6Mg6 cuboctahedra, and faces with ten MgLi4Mg8 cuboctahedra. There are four shorter (3.10 Å) and two longer (3.20 Å) Li–Li bond lengths. There are two shorter (3.07 Å) and two longer (3.10 Å) Li–Mg bond lengths. In the third Li site, Li is bonded in a 12-coordinate geometry to six Li and four Mg atoms. There are two shorter (3.03 Å) and two longer (3.06 Å) Li–Mg bond lengths. There are three inequivalent Mg sites. In the first Mg site, Mg is bonded to four Li and eight Mg atoms to form distorted MgLi4Mg8 cuboctahedra that share corners with six equivalent MgLi4Mg8 cuboctahedra, corners with twelve LiLi6Mg6 cuboctahedra, edges with four equivalent MgLi4Mg8 cuboctahedra, edges with six LiLi6Mg6 cuboctahedra, faces with four LiLi6Mg6 cuboctahedra, and faces with fourteen MgLi4Mg8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.12–3.20 Å. In the second Mg site, Mg is bonded to six Li and six Mg atoms to form distorted MgLi6Mg6 cuboctahedra that share corners with twelve MgLi4Mg8 cuboctahedra, edges with three equivalent MgLi4Mg8 cuboctahedra, edges with twelve LiLi8Mg4 cuboctahedra, faces with six LiLi6Mg6 cuboctahedra, and faces with twelve MgLi4Mg8 cuboctahedra. All Mg–Mg bond lengths are 3.20 Å. In the third Mg site, Mg is bonded to four Li and eight Mg atoms to form distorted MgLi4Mg8 cuboctahedra that share corners with twelve MgLi4Mg8 cuboctahedra, edges with seven MgLi4Mg8 cuboctahedra, edges with eight equivalent LiLi6Mg6 cuboctahedra, faces with eight LiLi6Mg6 cuboctahedra, and faces with ten MgLi4Mg8 cuboctahedra. Both Mg–Mg bond lengths are 3.20 Å.