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DOE OSTI · 1262121

Materials Data on Nb2Pd3Se8 by Materials Project

Abstract

Nb2Pd3Se8 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Nb5+ is bonded to six Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with two equivalent PdSe5 square pyramids, edges with two equivalent NbSe6 pentagonal pyramids, and edges with two equivalent PdSe5 square pyramids. There are a spread of Nb–Se bond distances ranging from 2.57–2.65 Å. There are two inequivalent Pd2+ sites. In the first Pd2+ site, Pd2+ is bonded in a square co-planar geometry to four Se2- atoms. There are two shorter (2.47 Å) and two longer (2.49 Å) Pd–Se bond lengths. In the second Pd2+ site, Pd2+ is bonded to five Se2- atoms to form PdSe5 square pyramids that share corners with two equivalent NbSe6 pentagonal pyramids, edges with two equivalent NbSe6 pentagonal pyramids, and edges with two equivalent PdSe5 square pyramids. There are four shorter (2.50 Å) and one longer (2.65 Å) Pd–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Nb5+ and one Pd2+ atom. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Nb5+ and two Pd2+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent Pd2+ atoms. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent Pd2+ atoms.

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2020-07-18. Materials Data on Nb2Pd3Se8 by Materials Project. https://doi.org/10.17188/1262121

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36 MATERIALS SCIENCE↗