Materials Data on Li2Mn2CoO8 by Materials Project

Abstract

Li2Mn2CoO8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three equivalent CoO6 octahedra and corners with six equivalent MnO6 octahedra. The corner-sharing octahedra tilt angles range from 54–59°. There are a spread of Li–O bond distances ranging from 1.95–2.00 Å. Mn5+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent LiO4 tetrahedra, edges with two equivalent MnO6 octahedra, and edges with two equivalent CoO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.89–1.96 Å. Co4+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent LiO4 tetrahedra and edges with four equivalent MnO6 octahedra. There is four shorter (1.85 Å) and two longer (1.95 Å) Co–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two equivalent Mn5+ atoms. In the second O2- site, O2- is bonded to one Li1+, two equivalent Mn5+, and one Co4+ atom to form distorted corner-sharing OLiMn2Co trigonal pyramids. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one Mn5+, and one Co4+ atom.