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DOE OSTI · 1305736

Materials Data on Li2MnF4 by Materials Project

Abstract

Li2MnF4 crystallizes in the orthorhombic Pnn2 space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.93–2.55 Å. In the second Li1+ site, Li1+ is bonded in a distorted see-saw-like geometry to four F1- atoms. There is two shorter (1.91 Å) and two longer (2.00 Å) Li–F bond length. In the third Li1+ site, Li1+ is bonded to four F1- atoms to form distorted corner-sharing LiF4 tetrahedra. There is two shorter (1.87 Å) and two longer (2.04 Å) Li–F bond length. In the fourth Li1+ site, Li1+ is bonded in a 4-coordinate geometry to six F1- atoms. There are a spread of Li–F bond distances ranging from 1.87–2.67 Å. In the fifth Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 trigonal pyramids that share corners with two MnF6 octahedra and a cornercorner with one LiF4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–69°. There are a spread of Li–F bond distances ranging from 1.88–1.97 Å. In the sixth Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five F1- atoms. There are a spread of Li–F bond distances ranging from 1.92–2.49 Å. There are three inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to six F1- atoms to form distorted MnF6 octahedra that share corners with two equivalent LiF4 trigonal pyramids and an edgeedge with one MnF6 octahedra. There are a spread of Mn–F bond distances ranging from 2.09–2.28 Å. In the second Mn2+ site, Mn2+ is bonded to six F1- atoms to form MnF6 octahedra that share corners with two equivalent LiF4 trigonal pyramids and an edgeedge with one MnF6 octahedra. There are a spread of Mn–F bond distances ranging from 2.08–2.33 Å. In the third Mn2+ site, Mn2+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Mn–F bond distances ranging from 2.02–2.61 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to two Li1+ and one Mn2+ atom. In the second F1- site, F1- is bonded to three Li1+ and one Mn2+ atom to form corner-sharing FLi3Mn tetrahedra. In the third F1- site, F1- is bonded in a 4-coordinate geometry to one Li1+ and three Mn2+ atoms. In the fourth F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two Mn2+ atoms. In the fifth F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two Mn2+ atoms. In the sixth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Mn2+ atom. In the seventh F1- site, F1- is bonded to three Li1+ and one Mn2+ atom to form corner-sharing FLi3Mn tetrahedra. In the eighth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Mn2+ atom.

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2020-08-03. Materials Data on Li2MnF4 by Materials Project. https://doi.org/10.17188/1305736

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