Materials Data on Li12Mg3Si4 by Materials Project
Li12Mg3Si4 crystallizes in the cubic I-43d space group. The structure is three-dimensional. Li is bonded in a 10-coordinate geometry to two equivalent Mg and three equivalent Si atoms. There are one shorter (2.79 Å) and one longer (2.80 Å) Li–Mg bond lengths. There are a spread of Li–Si bond distances ranging from 2.66–2.78 Å. Mg is bonded to eight equivalent Li and four equivalent Si atoms to form MgLi8Si4 cuboctahedra that share corners with eight equivalent SiLi9Mg3 cuboctahedra, edges with eight equivalent MgLi8Si4 cuboctahedra, and faces with four equivalent SiLi9Mg3 cuboctahedra. All Mg–Si bond lengths are 2.89 Å. Si is bonded to nine equivalent Li and three equivalent Mg atoms to form distorted SiLi9Mg3 cuboctahedra that share corners with six equivalent MgLi8Si4 cuboctahedra, edges with six equivalent SiLi9Mg3 cuboctahedra, faces with three equivalent MgLi8Si4 cuboctahedra, and faces with five equivalent SiLi9Mg3 cuboctahedra.