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DOE OSTI · 1306012

Materials Data on Li4FeOF5 by Materials Project

Abstract

Li4FeOF5 crystallizes in the monoclinic Cc 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 corners with two equivalent LiOF5 octahedra, corners with two equivalent FeOF5 octahedra, edges with two equivalent FeOF5 octahedra, and edges with eight LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 8–13°. The Li–O bond length is 1.98 Å. There are a spread of Li–F bond distances ranging from 2.02–2.25 Å. In the second Li1+ site, Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share corners with two equivalent LiOF5 octahedra, corners with two equivalent FeOF5 octahedra, edges with two equivalent FeOF5 octahedra, and edges with eight LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 11–14°. The Li–O bond length is 2.04 Å. There are a spread of Li–F bond distances ranging from 2.02–2.15 Å. In the third Li1+ site, Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share corners with six LiOF5 octahedra, edges with three equivalent FeOF5 octahedra, and edges with six LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 5–16°. The Li–O bond length is 2.05 Å. There are a spread of Li–F bond distances ranging from 2.01–2.22 Å. In the fourth Li1+ site, Li1+ is bonded to one O2- and five F1- atoms to form LiOF5 octahedra that share corners with two equivalent LiOF5 octahedra, corners with two equivalent FeOF5 octahedra, edges with two equivalent FeOF5 octahedra, and edges with eight LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 4–16°. The Li–O bond length is 1.94 Å. There are a spread of Li–F bond distances ranging from 1.94–2.25 Å. Fe3+ is bonded to one O2- and five F1- atoms to form FeOF5 octahedra that share corners with six LiOF5 octahedra and edges with nine LiOF5 octahedra. The corner-sharing octahedra tilt angles range from 4–14°. The Fe–O bond length is 1.81 Å. There are a spread of Fe–F bond distances ranging from 2.02–2.11 Å. O2- is bonded to four Li1+ and one Fe3+ atom to form OLi4Fe square pyramids that share corners with nine FLi4Fe square pyramids and edges with eight FLi4Fe square pyramids. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share a cornercorner with one OLi4Fe square pyramid, corners with eight FLi4Fe square pyramids, edges with two equivalent OLi4Fe square pyramids, and edges with six FLi4Fe square pyramids. In the second F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share a cornercorner with one OLi4Fe square pyramid, corners with eight FLi4Fe square pyramids, edges with two equivalent OLi4Fe square pyramids, and edges with six FLi4Fe square pyramids. In the third F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share corners with three equivalent OLi4Fe square pyramids, corners with six FLi4Fe square pyramids, an edgeedge with one OLi4Fe square pyramid, and edges with seven FLi4Fe square pyramids. In the fourth F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share corners with three equivalent OLi4Fe square pyramids, corners with six FLi4Fe square pyramids, an edgeedge with one OLi4Fe square pyramid, and edges with seven FLi4Fe square pyramids. In the fifth F1- site, F1- is bonded to four Li1+ and one Fe3+ atom to form FLi4Fe square pyramids that share a cornercorner with one OLi4Fe square pyramid, corners with eight FLi4Fe square pyramids, edges with two equivalent OLi4Fe square pyramids, and edges with six FLi4Fe square pyramids.

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2020-06-04. Materials Data on Li4FeOF5 by Materials Project. https://doi.org/10.17188/1306012

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