DOI: 10.17188/1307484
title: Materials Data on LiFeOF2 by Materials Project

description: LiFeOF2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to two O2- and two F1- atoms to form LiO2F2 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiO2F2 tetrahedra. The corner-sharing octahedra tilt angles range from 54–70°. There is one shorter (1.93 Å) and one longer (1.99 Å) Li–O bond length. Both Li–F bond lengths are 1.94 Å. In the second Li1+ site, Li1+ is bonded to two O2- and two F1- atoms to form LiO2F2 tetrahedra that share corners with seven FeO3F3 octahedra and corners with two equivalent LiOF3 tetrahedra. The corner-sharing octahedra tilt angles range from 51–70°. There is one shorter (1.88 Å) and one longer (2.02 Å) Li–O bond length. There is one shorter (1.92 Å) and one longer (1.96 Å) Li–F bond length. In the third Li1+ site, Li1+ is bonded to two O2- and two F1- atoms to form LiO2F2 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiO2F2 tetrahedra. The corner-sharing octahedra tilt angles range from 53–68°. There is one shorter (1.95 Å) and one longer (2.01 Å) Li–O bond length. There is one shorter (1.90 Å) and one longer (1.93 Å) Li–F bond length. In the fourth Li1+ site, Li1+ is bonded to one O2- and three F1- atoms to form LiOF3 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiO2F2 tetrahedra. The corner-sharing octahedra tilt angles range from 55–70°. The Li–O bond length is 2.01 Å. There are a spread of Li–F bond distances ranging from 1.89–2.00 Å. In the fifth Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with seven FeO3F3 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Li–F bond distances ranging from 1.90–1.96 Å. In the sixth Li1+ site, Li1+ is bonded to one O2- and three F1- atoms to form LiOF3 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–61°. The Li–O bond length is 1.97 Å. There are a spread of Li–F bond distances ranging from 1.94–1.96 Å. In the seventh Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–58°. There are a spread of Li–F bond distances ranging from 1.87–1.93 Å. In the eighth Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with seven FeO2F4 octahedra and corners with two equivalent LiOF3 tetrahedra. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Li–F bond distances ranging from 1.89–2.01 Å. There are eight inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to two O2- and four F1- atoms to form distorted FeO2F4 octahedra that share corners with eight LiO2F2 tetrahedra and edges with three FeO3F3 octahedra. There is one shorter (1.86 Å) and one longer (1.99 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 1.94–2.32 Å. In the second Fe3+ site, Fe3+ is bonded to three O2- and three F1- atoms to form FeO3F3 octahedra that share corners with six LiO2F2 tetrahedra and edges with five FeO2F4 octahedra. There are a spread of Fe–O bond distances ranging from 1.86–2.00 Å. There are a spread of Fe–F bond distances ranging from 2.05–2.25 Å. In the third Fe3+ site, Fe3+ is bonded to three O2- and three F1- atoms to form FeO3F3 octahedra that share corners with six LiO2F2 tetrahedra and edges with five FeO2F4 octahedra. There are a spread of Fe–O bond distances ranging from 1.86–1.99 Å. There are a spread of Fe–F bond distances ranging from 2.08–2.25 Å. In the fourth Fe3+ site, Fe3+ is bonded to two O2- and four F1- atoms to form distorted FeO2F4 octahedra that share corners with eight LiO2F2 tetrahedra and edges with three FeO3F3 octahedra. There is one shorter (1.88 Å) and one longer (2.01 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 1.94–2.28 Å. In the fifth Fe3+ site, Fe3+ is bonded to one O2- and five F1- atoms to form FeOF5 octahedra that share corners with eight LiO2F2 tetrahedra and edges with three FeO4F2 octahedra. The Fe–O bond length is 1.95 Å. There are a spread of Fe–F bond distances ranging from 1.92–2.16 Å. In the sixth Fe3+ site, Fe3+ is bonded to four O2- and two F1- atoms to form distorted FeO4F2 octahedra that share corners with six LiO2F2 tetrahedra and edges with five FeOF5 octahedra. There are a spread of Fe–O bond distances ranging from 1.87–2.07 Å. There are one shorter (2.06 Å) and one longer (2.37 Å) Fe–F bond lengths. In the seventh Fe3+ site, Fe3+ is bonded to three O2- and three F1- atoms to form FeO3F3 octahedra that share corners with six LiO2F2 tetrahedra and edges with five FeOF5 octahedra. There is two shorter (1.94 Å) and one longer (2.00 Å) Fe–O bond length. There are a spread of Fe–F bond distances ranging from 2.10–2.16 Å. In the eighth Fe3+ site, Fe3+ is bonded to three O2- and three F1- atoms to form FeO3F3 octahedra that share corners with eight LiO2F2 tetrahedra and edges with three FeO4F2 octahedra. There are a spread of Fe–O bond distances ranging from 1.90–2.11 Å. There are a spread of Fe–F bond distances ranging from 1.99–2.14 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to one Li1+ and three Fe3+ atoms to form corner-sharing OLiFe3 tetrahedra. In the second O2- site, O2- is bonded to one Li1+ and three Fe3+ atoms to form corner-sharing OLiFe3 tetrahedra. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the sixth O2- site, O2- is bonded to one Li1+ and three Fe3+ atoms to form distorted corner-sharing OLiFe3 tetrahedra. In the seventh O2- site, O2- is bonded to one Li1+ and three Fe3+ atoms to form distorted corner-sharing OLiFe3 tetrahedra. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Li1+ and three Fe3+ atoms. There are sixteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the second F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the third F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the fourth F1- site, F1- is bonded in a trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the fifth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the sixth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the seventh F1- site, F1- is bonded in a 4-coordinate geometry to one Li1+ and three Fe3+ atoms. In the eighth F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two Fe3+ atoms. In the ninth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the tenth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the eleventh F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Fe3+ atoms. In the twelfth F1- site, F1- is bonded in a distorted rectangular see-saw-like geometry to one Li1+ and three Fe3+ atoms. In the thirteenth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom. In the fourteenth F1- site, F1- is bonded in a 3-coordinate geometry to one Li1+ and two Fe3+ atoms. In the fifteenth F1- site, F1- is bonded in a distorted rectangular see-saw-like geometry to one Li1+ and three Fe3+ atoms. In the sixteenth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Fe3+ atom.