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DOE OSTI · 1297727

Materials Data on Li6Mn2O5F2 by Materials Project

Abstract

Li6Mn2O5F2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form distorted LiO4F square pyramids that share corners with three equivalent MnO4F2 octahedra, corners with five LiO4F square pyramids, a cornercorner with one LiO4F trigonal bipyramid, edges with three MnO4F2 octahedra, and edges with five LiO4F square pyramids. The corner-sharing octahedra tilt angles range from 5–13°. There are a spread of Li–O bond distances ranging from 2.00–2.31 Å. The Li–F bond length is 2.11 Å. In the second Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form LiO4F square pyramids that share corners with five LiO4F square pyramids, corners with four equivalent LiO4F trigonal bipyramids, edges with four MnO4F2 octahedra, edges with three LiO4F square pyramids, and an edgeedge with one LiO4F trigonal bipyramid. There are a spread of Li–O bond distances ranging from 2.01–2.20 Å. The Li–F bond length is 2.13 Å. In the third Li1+ site, Li1+ is bonded to three O2- and two F1- atoms to form distorted LiO3F2 square pyramids that share corners with three equivalent MnO4F2 octahedra, corners with five LiO4F square pyramids, a cornercorner with one LiO4F trigonal bipyramid, edges with three MnO4F2 octahedra, edges with three LiO4F square pyramids, and edges with two equivalent LiO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 3–18°. There are a spread of Li–O bond distances ranging from 1.91–2.02 Å. There are one shorter (2.27 Å) and one longer (2.49 Å) Li–F bond lengths. In the fourth Li1+ site, Li1+ is bonded to three O2- and two F1- atoms to form LiO3F2 square pyramids that share corners with eight LiO4F square pyramids, a cornercorner with one LiO4F trigonal bipyramid, edges with four MnO4F2 octahedra, and edges with four LiO4F square pyramids. There are a spread of Li–O bond distances ranging from 1.93–1.99 Å. There are one shorter (2.28 Å) and one longer (2.41 Å) Li–F bond lengths. In the fifth Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form LiO4F square pyramids that share corners with seven LiO4F square pyramids, corners with two equivalent LiO4F trigonal bipyramids, edges with four MnO4F2 octahedra, and edges with four LiO4F square pyramids. There are a spread of Li–O bond distances ranging from 1.94–2.22 Å. The Li–F bond length is 2.03 Å. In the sixth Li1+ site, Li1+ is bonded to four O2- and one F1- atom to form LiO4F trigonal bipyramids that share corners with nine LiO4F square pyramids, edges with four MnO4F2 octahedra, edges with three LiO4F square pyramids, and an edgeedge with one LiO4F trigonal bipyramid. There are a spread of Li–O bond distances ranging from 1.99–2.19 Å. The Li–F bond length is 2.08 Å. There are two inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to four O2- and two F1- atoms to form MnO4F2 octahedra that share corners with three equivalent MnO4F2 octahedra, corners with three equivalent LiO4F square pyramids, an edgeedge with one MnO4F2 octahedra, edges with ten LiO4F square pyramids, and an edgeedge with one LiO4F trigonal bipyramid. The corner-sharing octahedra tilt angles range from 1–8°. There are a spread of Mn–O bond distances ranging from 1.89–2.16 Å. There are one shorter (2.09 Å) and one longer (2.38 Å) Mn–F bond lengths. In the second Mn3+ site, Mn3+ is bonded to four O2- and two F1- atoms to form MnO4F2 octahedra that share corners with three equivalent MnO4F2 octahedra, corners with three equivalent LiO3F2 square pyramids, an edgeedge with one MnO4F2 octahedra, edges with eight LiO4F square pyramids, and edges with three equivalent LiO4F trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–8°. There are a spread of Mn–O bond distances ranging from 1.89–2.21 Å. There are one shorter (2.08 Å) and one longer (2.36 Å) Mn–F bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Li1+ and one Mn3+ atom to form OLi5Mn octahedra that share corners with three equivalent FLi4Mn2 octahedra, edges with three FLi4Mn2 octahedra, and edges with eight OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 6–17°. In the second O2- site, O2- is bonded to five Li1+ and one Mn3+ atom to form OLi5Mn octahedra that share corners with three equivalent OLi4Mn2 octahedra, edges with four FLi4Mn2 octahedra, and edges with seven OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 9–20°. In the third O2- site, O2- is bonded to four Li1+ and two equivalent Mn3+ atoms to form OLi4Mn2 octahedra that share corners with six FLi4Mn2 octahedra, edges with two FLi4Mn2 octahedra, and edges with eight OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 1–26°. In the fourth O2- site, O2- is bonded to four Li1+ and two Mn3+ atoms to form distorted OLi4Mn2 octahedra that share corners with six OLi5Mn octahedra, edges with four FLi4Mn2 octahedra, and edges with six OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 8–20°. In the fifth O2- site, O2- is bonded to four Li1+ and two equivalent Mn3+ atoms to form OLi4Mn2 octahedra that share corners with three equivalent OLi4Mn2 octahedra, corners with three equivalent FLi4Mn2 octahedra, edges with three FLi4Mn2 octahedra, and edges with seven OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 8–23°. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four Li1+ and two Mn3+ atoms to form distorted FLi4Mn2 octahedra that share corners with six OLi5Mn octahedra, edges with two equivalent FLi4Mn2 octahedra, and edges with eight OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 5–19°. In the second F1- site, F1- is bonded to four Li1+ and two Mn3+ atoms to form distorted FLi4Mn2 octahedra that share corners with six OLi4Mn2 octahedra, edges with two equivalent FLi4Mn2 octahedra, and edges with eight OLi5Mn octahedra. The corner-sharing octahedra tilt angles range from 1–26°.

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2020-08-03. Materials Data on Li6Mn2O5F2 by Materials Project. https://doi.org/10.17188/1297727

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