Materials Data on Li2Mn3F8 by Materials Project

Abstract

Li2Mn3F8 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Li1+ is bonded to six F1- atoms to form distorted LiF6 octahedra that share corners with two equivalent LiF6 octahedra, corners with two equivalent MnF4 tetrahedra, and an edgeedge with one LiF6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Li–F bond distances ranging from 1.98–2.37 Å. There are three inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Mn–F bond distances ranging from 2.10–2.52 Å. In the second Mn2+ site, Mn2+ is bonded to four equivalent F1- atoms to form MnF4 tetrahedra that share corners with eight equivalent LiF6 octahedra. The corner-sharing octahedra tilt angles range from 62–72°. All Mn–F bond lengths are 2.02 Å. In the third Mn2+ site, Mn2+ is bonded in a distorted body-centered cubic geometry to eight F1- atoms. There are four shorter (2.15 Å) and four longer (2.54 Å) Mn–F bond lengths. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to one Li1+ and three Mn2+ atoms. In the second F1- site, F1- is bonded to two equivalent Li1+ and two Mn2+ atoms to form a mixture of distorted edge and corner-sharing FLi2Mn2 tetrahedra. In the third F1- site, F1- is bonded to one Li1+ and three Mn2+ atoms to form distorted FLiMn3 tetrahedra that share corners with eleven FLi2Mn2 tetrahedra and edges with two FLiMn3 tetrahedra. In the fourth F1- site, F1- is bonded to two equivalent Li1+ and two equivalent Mn2+ atoms to form distorted FLi2Mn2 tetrahedra that share corners with eight FLi2Mn2 tetrahedra and edges with four FLiMn3 tetrahedra.