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DOE OSTI · 1286610

Materials Data on Nb3CoS6 by Materials Project

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Abstract

CoNb3S6 is Ilmenite-like structured and crystallizes in the hexagonal P6_322 space group. The structure is three-dimensional. there are two inequivalent Nb+3.33+ sites. In the first Nb+3.33+ site, Nb+3.33+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with three equivalent CoS6 octahedra, edges with six NbS6 pentagonal pyramids, and a faceface with one CoS6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are three shorter (2.48 Å) and three longer (2.51 Å) Nb–S bond lengths. In the second Nb+3.33+ site, Nb+3.33+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with six equivalent CoS6 octahedra and edges with six equivalent NbS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 46°. All Nb–S bond lengths are 2.49 Å. Co2+ is bonded to six equivalent S2- atoms to form CoS6 octahedra that share corners with twelve NbS6 pentagonal pyramids and faces with two equivalent NbS6 pentagonal pyramids. All Co–S bond lengths are 2.37 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.33+ and one Co2+ atom.

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36 MATERIALS SCIENCECo-Nb-Scrystal structureNb3CoS6

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2020-07-15. Materials Data on Nb3CoS6 by Materials Project. https://doi.org/10.17188/1286610

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36 MATERIALS SCIENCE↗