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DOE OSTI · 1730846

Materials Data on K(Nb3Se4)2 by Materials Project

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Abstract

K(Nb3Se4)2 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All K–Se bond lengths are 3.34 Å. Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.85 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 one K1+ and four equivalent Nb+2.50+ atoms.

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36 MATERIALS SCIENCEcrystal structureK(Nb3Se4)2K-Nb-Se

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2020-04-29. Materials Data on K(Nb3Se4)2 by Materials Project. https://doi.org/10.17188/1730846

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