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DOE OSTI · 1730534

Materials Data on Nb6CuSe8 by Materials Project

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Abstract

Nb6CuSe8 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted face, edge, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–56°. There are a spread of Nb–Se bond distances ranging from 2.60–2.80 Å. Cu1+ is bonded in a distorted hexagonal planar geometry to six equivalent Se2- atoms. All Cu–Se bond lengths are 3.23 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six equivalent Nb+2.50+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to four equivalent Nb+2.50+ and one Cu1+ atom.

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36 MATERIALS SCIENCEcrystal structureCu-Nb-SeNb6CuSe8

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2020-05-02. Materials Data on Nb6CuSe8 by Materials Project. https://doi.org/10.17188/1730534

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