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DOE OSTI · 1698443

Materials Data on Nb3CoSe6 by Materials Project

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Abstract

Nb3CoSe6 is Ilmenite-like structured and crystallizes in the trigonal P312 space group. The structure is three-dimensional. there are three inequivalent Nb+3.33+ sites. In the first Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with three equivalent CoSe6 octahedra, edges with six NbSe6 pentagonal pyramids, and a faceface with one CoSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are three shorter (2.61 Å) and three longer (2.64 Å) Nb–Se bond lengths. In the second Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with three equivalent CoSe6 octahedra, edges with six NbSe6 pentagonal pyramids, and a faceface with one CoSe6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are three shorter (2.62 Å) and three longer (2.64 Å) Nb–Se bond lengths. In the third Nb+3.33+ site, Nb+3.33+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with six CoSe6 octahedra and edges with six NbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 48°. There are three shorter (2.61 Å) and three longer (2.62 Å) Nb–Se bond lengths. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six equivalent Se2- atoms to form CoSe6 octahedra that share corners with twelve NbSe6 pentagonal pyramids and faces with two equivalent NbSe6 pentagonal pyramids. All Co–Se bond lengths are 2.49 Å. In the second Co2+ site, Co2+ is bonded to six equivalent Se2- atoms to form CoSe6 octahedra that share corners with twelve NbSe6 pentagonal pyramids and faces with two equivalent NbSe6 pentagonal pyramids. All Co–Se bond lengths are 2.49 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb+3.33+ and one Co2+ atom. In the second Se2- site, Se2- 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-Secrystal structureNb3CoSe6

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2020-04-30. Materials Data on Nb3CoSe6 by Materials Project. https://doi.org/10.17188/1698443

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36 MATERIALS SCIENCE↗