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DOE OSTI · 1757413

Materials Data on Nb2Se3 by Materials Project

Abstract

Nb2Se3 crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one Nb2Se3 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Nb3+ sites. In the first Nb3+ site, Nb3+ is bonded to six Se2- atoms to form a mixture of corner, edge, and face-sharing NbSe6 octahedra. There are three shorter (2.61 Å) and three longer (2.70 Å) Nb–Se bond lengths. In the second Nb3+ site, Nb3+ is bonded to six Se2- atoms to form a mixture of distorted corner, edge, and face-sharing NbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 44°. All Nb–Se bond lengths are 2.62 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six Nb3+ atoms to form distorted edge-sharing SeNb6 pentagonal pyramids. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Nb3+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Nb3+ atoms.

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2020-09-03. Materials Data on Nb2Se3 by Materials Project. https://doi.org/10.17188/1757413

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36 MATERIALS SCIENCE↗