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DOE OSTI · 1305475

Materials Data on Li9Cr3(WO4)7 by Materials Project

Abstract

Li9Cr3(WO4)7 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.99–2.49 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.01–2.66 Å. There are three inequivalent W+5.43+ sites. In the first W+5.43+ site, W+5.43+ is bonded to six O2- atoms to form distorted WO6 octahedra that share corners with six equivalent CrO6 octahedra and edges with three equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are three shorter (1.84 Å) and three longer (2.20 Å) W–O bond lengths. In the second W+5.43+ site, W+5.43+ is bonded to six O2- atoms to form distorted WO6 octahedra that share edges with two equivalent CrO6 octahedra and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 1.82–2.20 Å. In the third W+5.43+ site, W+5.43+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with two equivalent CrO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of W–O bond distances ranging from 1.79–1.84 Å. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent WO6 octahedra, corners with two equivalent WO4 tetrahedra, and edges with two equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of Cr–O bond distances ranging from 1.99–2.38 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Li1+, three W+5.43+, and one Cr3+ atom to form edge-sharing OLi2CrW3 octahedra. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Li1+, one W+5.43+, and one Cr3+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to one Li1+, one W+5.43+, and one Cr3+ atom. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to three equivalent Li1+ and three equivalent W+5.43+ atoms. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Li1+ and one W+5.43+ atom. In the sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to three Li1+ and one W+5.43+ atom. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Li1+, one W+5.43+, and one Cr3+ atom. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to two equivalent Li1+ and one W+5.43+ atom.

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2020-07-15. Materials Data on Li9Cr3(WO4)7 by Materials Project. https://doi.org/10.17188/1305475

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