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DOE OSTI · 1191046

Materials Data on Lu4C7 by Materials Project

Abstract

Lu4C7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded to seven C+1.71- atoms to form distorted LuC7 octahedra that share corners with two equivalent LuC7 octahedra, a cornercorner with one CLu4C trigonal bipyramid, and edges with five equivalent LuC7 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Lu–C bond distances ranging from 2.43–2.95 Å. In the second Lu3+ site, Lu3+ is bonded in a 9-coordinate geometry to nine C+1.71- atoms. There are a spread of Lu–C bond distances ranging from 2.37–2.77 Å. There are four inequivalent C+1.71- sites. In the first C+1.71- site, C+1.71- is bonded to six Lu3+ atoms to form CLu6 octahedra that share corners with two equivalent CLu4C trigonal bipyramids, edges with two equivalent CLu6 octahedra, and edges with four equivalent CLu4C trigonal bipyramids. In the second C+1.71- site, C+1.71- is bonded to four Lu3+ and one C+1.71- atom to form distorted CLu4C trigonal bipyramids that share a cornercorner with one LuC7 octahedra, a cornercorner with one CLu6 octahedra, corners with six equivalent CLu4C trigonal bipyramids, and edges with two equivalent CLu6 octahedra. The corner-sharing octahedra tilt angles range from 31–60°. The C–C bond length is 1.32 Å. In the third C+1.71- site, C+1.71- is bonded in a 3-coordinate geometry to four Lu3+ and two C+1.71- atoms. The C–C bond length is 1.33 Å. In the fourth C+1.71- site, C+1.71- is bonded in a 6-coordinate geometry to five Lu3+ and one C+1.71- atom.

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2020-07-15. Materials Data on Lu4C7 by Materials Project. https://doi.org/10.17188/1191046

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36 MATERIALS SCIENCE↗