Materials Data on Li2FeOF3 by Materials Project
Li2FeOF3 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share a cornercorner with one LiO2F4 octahedra, corners with four FeO2F4 octahedra, edges with two FeO2F4 octahedra, and edges with six LiO2F4 octahedra. The corner-sharing octahedra tilt angles range from 6–22°. The Li–O bond length is 2.20 Å. There are a spread of Li–F bond distances ranging from 2.02–2.29 Å. In the second Li1+ site, Li1+ is bonded to two O2- and four F1- atoms to form distorted LiO2F4 octahedra that share corners with four LiOF5 octahedra, edges with four FeO2F4 octahedra, and edges with five LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 4–24°. There are one shorter (2.03 Å) and one longer (2.09 Å) Li–O bond lengths. There are a spread of Li–F bond distances ranging from 1.97–2.45 Å. In the third Li1+ site, Li1+ is bonded to two O2- and four F1- atoms to form LiO2F4 octahedra that share corners with two equivalent LiO2F4 octahedra, corners with two FeO2F4 octahedra, edges with four FeO2F4 octahedra, and edges with five LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 3–24°. There are one shorter (2.01 Å) and one longer (2.32 Å) Li–O bond lengths. There are a spread of Li–F bond distances ranging from 1.99–2.46 Å. In the fourth Li1+ site, Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share a cornercorner with one LiO2F4 octahedra, corners with four FeO2F4 octahedra, edges with two FeO2F4 octahedra, and edges with six LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 4–17°. The Li–O bond length is 2.15 Å. There are a spread of Li–F bond distances ranging from 2.03–2.17 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to two O2- and four F1- atoms to form FeO2F4 octahedra that share corners with five LiOF5 octahedra, edges with two equivalent FeO2F4 octahedra, and edges with six LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 6–13°. Both Fe–O bond lengths are 1.94 Å. There are a spread of Fe–F bond distances ranging from 1.99–2.13 Å. In the second Fe3+ site, Fe3+ is bonded to two O2- and four F1- atoms to form FeO2F4 octahedra that share corners with five LiOF5 octahedra, edges with two equivalent FeO2F4 octahedra, and edges with six LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 3–22°. There is one shorter (1.92 Å) and one longer (1.95 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 2.01–2.11 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and two Fe3+ atoms to form OLi3Fe2 square pyramids that share corners with two equivalent FLi4Fe square pyramids, corners with two equivalent OLi3Fe2 trigonal bipyramids, edges with three FLi4Fe square pyramids, and an edgeedge with one OLi3Fe2 trigonal bipyramid. In the second O2- site, O2- is bonded to three Li1+ and two Fe3+ atoms to form distorted OLi3Fe2 trigonal bipyramids that share corners with two equivalent OLi3Fe2 square pyramids, corners with two equivalent FLi4Fe square pyramids, an edgeedge with one OLi3Fe2 square pyramid, and edges with three FLi4Fe square pyramids. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form distorted FLi4Fe square pyramids that share corners with two equivalent FLi4Fe square pyramids, corners with two equivalent OLi3Fe2 trigonal bipyramids, an edgeedge with one FLi4Fe square pyramid, edges with two equivalent OLi3Fe2 square pyramids, and an edgeedge with one OLi3Fe2 trigonal bipyramid. In the second F1- site, F1- is bonded in a rectangular see-saw-like geometry to two Li1+ and two Fe3+ atoms. In the third F1- site, F1- is bonded in a rectangular see-saw-like geometry to two Li1+ and two Fe3+ atoms. In the fourth F1- site, F1- is bonded in a rectangular see-saw-like geometry to three Li1+ and one Fe3+ atom. In the fifth F1- site, F1- is bonded in a distorted see-saw-like geometry to three Li1+ and one Fe3+ atom. In the sixth F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share corners with two equivalent OLi3Fe2 square pyramids, corners with two equivalent FLi4Fe square pyramids, an edgeedge with one OLi3Fe2 square pyramid, an edgeedge with one FLi4Fe square pyramid, and edges with two equivalent OLi3Fe2 trigonal bipyramids.