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DOE OSTI · 1295160

Materials Data on Li3Mn4O8 by Materials Project

Abstract

Li3Mn4O8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with four LiO6 octahedra, corners with four MnO6 octahedra, corners with two MnO5 square pyramids, edges with two equivalent LiO6 octahedra, edges with two MnO5 square pyramids, and faces with two MnO6 octahedra. The corner-sharing octahedra tilt angles range from 39–53°. There are a spread of Li–O bond distances ranging from 2.05–2.21 Å. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with eight equivalent LiO6 octahedra, corners with four equivalent MnO5 square pyramids, edges with four equivalent MnO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 39–53°. There are two shorter (2.00 Å) and four longer (2.29 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with eight equivalent LiO6 octahedra, corners with four equivalent MnO5 square pyramids, edges with four equivalent MnO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 39–53°. There are two shorter (2.00 Å) and four longer (2.29 Å) Li–O bond lengths. There are four inequivalent Mn+3.25+ sites. In the first Mn+3.25+ site, Mn+3.25+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four equivalent LiO6 octahedra, corners with six MnO5 square pyramids, edges with two equivalent LiO6 octahedra, edges with two equivalent MnO6 octahedra, and faces with two equivalent LiO6 octahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Mn–O bond distances ranging from 1.94–2.11 Å. In the second Mn+3.25+ site, Mn+3.25+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four equivalent LiO6 octahedra, corners with six MnO5 square pyramids, edges with two equivalent LiO6 octahedra, edges with two equivalent MnO6 octahedra, and faces with two equivalent LiO6 octahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Mn–O bond distances ranging from 1.94–2.11 Å. In the third Mn+3.25+ site, Mn+3.25+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with four LiO6 octahedra, corners with six MnO6 octahedra, edges with three LiO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 46–79°. There are a spread of Mn–O bond distances ranging from 1.95–2.14 Å. In the fourth Mn+3.25+ site, Mn+3.25+ is bonded to five O2- atoms to form distorted MnO5 square pyramids that share corners with four LiO6 octahedra, corners with six MnO6 octahedra, edges with three LiO6 octahedra, and edges with two equivalent MnO5 square pyramids. The corner-sharing octahedra tilt angles range from 46–79°. There are a spread of Mn–O bond distances ranging from 1.95–2.14 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to two Li1+ and three Mn+3.25+ atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the second O2- site, O2- is bonded to two Li1+ and three Mn+3.25+ atoms to form a mixture of distorted edge and corner-sharing OLi2Mn3 trigonal bipyramids. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+ and three Mn+3.25+ atoms. In the fourth O2- site, O2- is bonded to three Li1+ and two equivalent Mn+3.25+ atoms to form a mixture of distorted edge and corner-sharing OLi3Mn2 trigonal bipyramids. In the fifth O2- site, O2- is bonded to three Li1+ and two equivalent Mn+3.25+ atoms to form a mixture of distorted edge and corner-sharing OLi3Mn2 trigonal bipyramids. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Li1+ and three Mn+3.25+ atoms.

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2020-05-03. Materials Data on Li3Mn4O8 by Materials Project. https://doi.org/10.17188/1295160

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