Materials Data on Li14Mn2O9 by Materials Project
Li14Mn2O9 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.90–2.40 Å. In the second Li1+ site, Li1+ is bonded to four equivalent O2- atoms to form distorted LiO4 tetrahedra that share corners with two equivalent MnO4 tetrahedra, corners with eight LiO4 tetrahedra, an edgeedge with one MnO4 tetrahedra, and edges with four LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.90–2.23 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three equivalent MnO4 tetrahedra, corners with seven LiO4 tetrahedra, and edges with three equivalent LiO4 tetrahedra. There are three shorter (2.01 Å) and one longer (2.12 Å) Li–O bond lengths. Mn2+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with nine LiO4 tetrahedra and edges with three equivalent LiO4 tetrahedra. There are one shorter (2.01 Å) and three longer (2.05 Å) Mn–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 7-coordinate geometry to six Li1+ and one Mn2+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to six equivalent Li1+ and one Mn2+ atom. In the third O2- site, O2- is bonded in a body-centered cubic geometry to eight Li1+ atoms.