Materials Data on Li3Mn2O4 by Materials Project
Li3Mn2O4 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four Li1+ and four O2- atoms to form LiLi4O4 tetrahedra that share corners with twelve MnO6 octahedra, corners with six equivalent OLi4Mn3 pentagonal bipyramids, corners with four equivalent LiLi4O4 tetrahedra, faces with four LiLi2O6 octahedra, and faces with two equivalent OLi4Mn3 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 52–58°. There is two shorter (1.86 Å) and two longer (1.93 Å) Li–Li bond length. All Li–O bond lengths are 1.90 Å. In the second Li1+ site, Li1+ is bonded to two equivalent Li1+ and six O2- atoms to form distorted LiLi2O6 octahedra that share corners with six equivalent MnO6 octahedra, corners with four equivalent OLi4Mn3 pentagonal bipyramids, edges with six MnO6 octahedra, faces with six LiLi2O6 octahedra, and faces with two equivalent LiLi4O4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. There are four shorter (2.21 Å) and two longer (2.27 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded to two equivalent Li1+ and six O2- atoms to form distorted LiLi2O6 octahedra that share corners with six equivalent MnO6 octahedra, corners with four equivalent OLi4Mn3 pentagonal bipyramids, edges with six MnO6 octahedra, faces with six LiLi2O6 octahedra, and faces with two equivalent LiLi4O4 tetrahedra. The corner-sharing octahedra tilt angles range from 1–7°. There are two shorter (2.08 Å) and four longer (2.19 Å) Li–O bond lengths. There are two inequivalent Mn+2.50+ sites. In the first Mn+2.50+ site, Mn+2.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent LiLi2O6 octahedra, corners with six equivalent LiLi4O4 tetrahedra, edges with six LiLi2O6 octahedra, and edges with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 1–7°. There are two shorter (2.16 Å) and four longer (2.25 Å) Mn–O bond lengths. In the second Mn+2.50+ site, Mn+2.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent LiLi2O6 octahedra, corners with six equivalent LiLi4O4 tetrahedra, edges with six LiLi2O6 octahedra, and edges with six MnO6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are two shorter (1.98 Å) and four longer (2.22 Å) Mn–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 7-coordinate geometry to four Li1+ and three Mn+2.50+ atoms. In the second O2- site, O2- is bonded to four Li1+ and three Mn+2.50+ atoms to form distorted OLi4Mn3 pentagonal bipyramids that share corners with four LiLi2O6 octahedra, corners with six equivalent OLi4Mn3 pentagonal bipyramids, corners with three equivalent LiLi4O4 tetrahedra, edges with three equivalent OLi4Mn3 pentagonal bipyramids, a faceface with one OLi4Mn3 pentagonal bipyramid, and a faceface with one LiLi4O4 tetrahedra. The corner-sharing octahedra tilt angles range from 3–113°.