Materials Data on Li2Mn2C2O7 by Materials Project

Abstract

Li2Mn2C2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.87–1.92 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share a cornercorner with one MnO5 square pyramid and an edgeedge with one MnO5 trigonal bipyramid. There are a spread of Li–O bond distances ranging from 1.90–2.27 Å. There are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to five O2- atoms to form distorted MnO5 trigonal bipyramids that share corners with two equivalent MnO5 square pyramids, edges with two equivalent MnO5 square pyramids, an edgeedge with one LiO4 tetrahedra, and an edgeedge with one MnO5 trigonal bipyramid. There are a spread of Mn–O bond distances ranging from 2.07–2.33 Å. In the second Mn2+ site, Mn2+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with two equivalent MnO5 square pyramids, a cornercorner with one LiO4 tetrahedra, corners with two equivalent MnO5 trigonal bipyramids, and edges with two equivalent MnO5 trigonal bipyramids. There are a spread of Mn–O bond distances ranging from 2.05–2.43 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of C–O bond distances ranging from 1.27–1.32 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.29 Å) and one longer (1.32 Å) C–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mn2+ and one C4+ atom. In the second O2- site, O2- is bonded to four Mn2+ atoms to form a mixture of distorted corner and edge-sharing OMn4 tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one C4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Mn2+, and one C4+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one C4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Mn2+ and one C4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+, one Mn2+, and one C4+ atom.