Materials Data on Li8Mn(O2F)2 by Materials Project

Abstract

Li8Mn(O2F)2 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are five inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two equivalent MnO2F2 tetrahedra, corners with eight LiO3F tetrahedra, and edges with four LiO2F2 tetrahedra. There are a spread of Li–O bond distances ranging from 1.94–2.08 Å. In the second Li1+ site, Li1+ is bonded in a distorted trigonal planar geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.95–2.51 Å. In the third Li1+ site, Li1+ is bonded to two O2- and two equivalent F1- atoms to form LiO2F2 tetrahedra that share corners with three equivalent MnO2F2 tetrahedra, corners with seven LiO2F2 tetrahedra, and edges with three LiO4 tetrahedra. There is one shorter (1.86 Å) and one longer (2.01 Å) Li–O bond length. Both Li–F bond lengths are 1.96 Å. In the fourth Li1+ site, Li1+ is bonded to three O2- and one F1- atom to form LiO3F tetrahedra that share corners with two equivalent MnO2F2 tetrahedra, corners with nine LiO4 tetrahedra, and edges with four LiO2F2 tetrahedra. There are one shorter (1.98 Å) and two longer (2.03 Å) Li–O bond lengths. The Li–F bond length is 2.05 Å. In the fifth Li1+ site, Li1+ is bonded to three O2- and one F1- atom to form distorted LiO3F tetrahedra that share corners with eleven LiO4 tetrahedra, an edgeedge with one MnO2F2 tetrahedra, and edges with three LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.97–2.18 Å. The Li–F bond length is 2.06 Å. Mn2+ is bonded to two O2- and two equivalent F1- atoms to form MnO2F2 tetrahedra that share corners with twelve LiO4 tetrahedra and edges with two equivalent LiO3F tetrahedra. There is one shorter (1.93 Å) and one longer (2.02 Å) Mn–O bond length. Both Mn–F bond lengths are 2.14 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Li1+ and one Mn2+ atom to form OLi4Mn trigonal bipyramids that share corners with six equivalent FLi4Mn trigonal bipyramids. In the second O2- site, O2- is bonded in a 7-coordinate geometry to seven Li1+ atoms. In the third O2- site, O2- is bonded in a 7-coordinate geometry to six Li1+ and one Mn2+ atom. F1- is bonded to four Li1+ and one Mn2+ atom to form FLi4Mn trigonal bipyramids that share corners with three equivalent OLi4Mn trigonal bipyramids and corners with three equivalent FLi4Mn trigonal bipyramids.