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DOE OSTI · 1307297

Materials Data on Li2Co2OF6 by Materials Project

Abstract

Li2Co2OF6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with six CoOF5 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–58°. There are a spread of Li–F bond distances ranging from 1.87–1.95 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with five CoOF5 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–61°. There are a spread of Li–F bond distances ranging from 1.90–1.99 Å. In the third Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with five CoOF5 octahedra and corners with two equivalent LiOF3 tetrahedra. The corner-sharing octahedra tilt angles range from 39–61°. There are a spread of Li–F bond distances ranging from 1.88–1.95 Å. In the fourth Li1+ site, Li1+ is bonded to one O2- and three F1- atoms to form LiOF3 tetrahedra that share corners with six CoOF5 octahedra and corners with two equivalent LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–62°. The Li–O bond length is 2.00 Å. There are a spread of Li–F bond distances ranging from 1.90–1.95 Å. There are four inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to one O2- and five F1- atoms to form CoOF5 octahedra that share a cornercorner with one CoOF5 octahedra, corners with seven LiF4 tetrahedra, and edges with two equivalent CoO2F4 octahedra. The corner-sharing octahedral tilt angles are 14°. The Co–O bond length is 1.80 Å. There are a spread of Co–F bond distances ranging from 1.92–2.13 Å. In the second Co3+ site, Co3+ is bonded to two O2- and four F1- atoms to form CoO2F4 octahedra that share a cornercorner with one CoOF5 octahedra, corners with four LiF4 tetrahedra, and edges with three CoOF5 octahedra. The corner-sharing octahedral tilt angles are 24°. There is one shorter (1.91 Å) and one longer (2.07 Å) Co–O bond length. There are a spread of Co–F bond distances ranging from 1.86–2.08 Å. In the third Co3+ site, Co3+ is bonded to one O2- and five F1- atoms to form CoOF5 octahedra that share a cornercorner with one CoOF5 octahedra, corners with four LiF4 tetrahedra, and edges with three CoO2F4 octahedra. The corner-sharing octahedral tilt angles are 14°. The Co–O bond length is 1.91 Å. There are a spread of Co–F bond distances ranging from 1.82–2.05 Å. In the fourth Co3+ site, Co3+ is bonded to one O2- and five F1- atoms to form CoOF5 octahedra that share a cornercorner with one CoO2F4 octahedra, corners with seven LiF4 tetrahedra, and edges with two equivalent CoOF5 octahedra. The corner-sharing octahedral tilt angles are 24°. The Co–O bond length is 1.87 Å. There are a spread of Co–F bond distances ranging from 1.90–2.09 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Li1+ and two Co3+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to three Co3+ atoms. There are twelve inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal planar geometry to two Li1+ and one Co3+ atom. In the second F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co3+ atoms. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Co3+ atom. In the fourth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co3+ atoms. In the fifth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Co3+ atom. In the sixth F1- site, F1- is bonded in a T-shaped geometry to three Co3+ atoms. In the seventh F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Co3+ atom. In the eighth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co3+ atoms. In the ninth F1- site, F1- is bonded in a bent 150 degrees geometry to one Li1+ and one Co3+ atom. In the tenth F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co3+ atoms. In the eleventh F1- site, F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co3+ atoms. In the twelfth F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Co3+ atom.

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2020-04-29. Materials Data on Li2Co2OF6 by Materials Project. https://doi.org/10.17188/1307297

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36 MATERIALS SCIENCE↗