Materials Data on Li3AlN2 by Materials Project
Li3AlN2 crystallizes in the cubic Ia-3 space group. The structure is three-dimensional. Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with four equivalent AlN4 tetrahedra, corners with twelve equivalent LiN4 tetrahedra, edges with two equivalent AlN4 tetrahedra, and edges with four equivalent LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.07–2.18 Å. Al3+ is bonded to four N3- atoms to form AlN4 tetrahedra that share corners with four equivalent AlN4 tetrahedra, corners with twelve equivalent LiN4 tetrahedra, and edges with six equivalent LiN4 tetrahedra. There is one shorter (1.90 Å) and three longer (1.94 Å) Al–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a body-centered cubic geometry to six equivalent Li1+ and two equivalent Al3+ atoms. In the second N3- site, N3- is bonded in a distorted body-centered cubic geometry to six equivalent Li1+ and two equivalent Al3+ atoms.