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DOE OSTI · 1744667

Materials Data on RbNb2PSe10 by Materials Project

Abstract

RbNb2PSe10 crystallizes in the monoclinic Pc space group. The structure is three-dimensional. Rb1+ is bonded in a 10-coordinate geometry to ten Se+1.40- atoms. There are a spread of Rb–Se bond distances ranging from 3.64–4.14 Å. There are two inequivalent Nb4+ sites. In the first Nb4+ site, Nb4+ is bonded to eight Se+1.40- atoms to form NbSe8 hexagonal bipyramids that share an edgeedge with one PSe4 tetrahedra and faces with two equivalent NbSe8 hexagonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.64–2.82 Å. In the second Nb4+ site, Nb4+ is bonded to eight Se+1.40- atoms to form distorted NbSe8 hexagonal bipyramids that share an edgeedge with one PSe4 tetrahedra and faces with two equivalent NbSe8 hexagonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.64–2.80 Å. P5+ is bonded to four Se+1.40- atoms to form PSe4 tetrahedra that share edges with two NbSe8 hexagonal bipyramids. There are a spread of P–Se bond distances ranging from 2.17–2.26 Å. There are ten inequivalent Se+1.40- sites. In the first Se+1.40- site, Se+1.40- is bonded in a 2-coordinate geometry to two Nb4+ and one Se+1.40- atom. The Se–Se bond length is 2.32 Å. In the second Se+1.40- site, Se+1.40- is bonded in a 2-coordinate geometry to one Rb1+, two Nb4+, and one Se+1.40- atom. The Se–Se bond length is 2.36 Å. In the third Se+1.40- site, Se+1.40- is bonded in a distorted L-shaped geometry to one Rb1+, one Nb4+, and one P5+ atom. In the fourth Se+1.40- site, Se+1.40- is bonded in a 3-coordinate geometry to two Nb4+ and one P5+ atom. In the fifth Se+1.40- site, Se+1.40- is bonded in a 2-coordinate geometry to one Rb1+, two Nb4+, and one Se+1.40- atom. In the sixth Se+1.40- site, Se+1.40- is bonded in a 4-coordinate geometry to one Rb1+, two Nb4+, and one Se+1.40- atom. The Se–Se bond length is 2.34 Å. In the seventh Se+1.40- site, Se+1.40- is bonded in a 2-coordinate geometry to two equivalent Rb1+, one Nb4+, and one P5+ atom. In the eighth Se+1.40- site, Se+1.40- is bonded in a 1-coordinate geometry to two equivalent Rb1+ and one P5+ atom. In the ninth Se+1.40- site, Se+1.40- is bonded in a 4-coordinate geometry to one Rb1+, two Nb4+, and one Se+1.40- atom. In the tenth Se+1.40- site, Se+1.40- is bonded in a 2-coordinate geometry to one Rb1+, two Nb4+, and one Se+1.40- atom.

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2020-05-02. Materials Data on RbNb2PSe10 by Materials Project. https://doi.org/10.17188/1744667

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36 MATERIALS SCIENCE↗