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DOE OSTI · 1712021

Materials Data on Nb4V3FeSe20 by Materials Project

Abstract

Nb4V3FeSe20 crystallizes in the monoclinic Pm space group. The structure is two-dimensional and consists of one Nb4V3FeSe20 sheet oriented in the (1, 0, -1) direction. there are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.70- atoms. There are a spread of Nb–Se bond distances ranging from 2.65–2.77 Å. In the second Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.70- atoms. There are a spread of Nb–Se bond distances ranging from 2.65–2.80 Å. In the third Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.70- atoms. There are a spread of Nb–Se bond distances ranging from 2.65–2.84 Å. In the fourth Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.70- atoms. There are a spread of Nb–Se bond distances ranging from 2.66–2.77 Å. There are three inequivalent V4+ sites. In the first V4+ site, V4+ is bonded to six Se+1.70- atoms to form edge-sharing VSe6 octahedra. There are a spread of V–Se bond distances ranging from 2.42–2.62 Å. In the second V4+ site, V4+ is bonded to six Se+1.70- atoms to form edge-sharing VSe6 octahedra. There are a spread of V–Se bond distances ranging from 2.42–2.65 Å. In the third V4+ site, V4+ is bonded to six Se+1.70- atoms to form distorted VSe6 octahedra that share edges with two equivalent VSe6 octahedra and edges with two equivalent FeSe6 octahedra. There are a spread of V–Se bond distances ranging from 2.33–2.70 Å. Fe2+ is bonded to six Se+1.70- atoms to form FeSe6 octahedra that share edges with two equivalent VSe6 octahedra and edges with two equivalent FeSe6 octahedra. There are a spread of Fe–Se bond distances ranging from 2.35–2.48 Å. There are twenty inequivalent Se+1.70- sites. In the first Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the second Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the third Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the fourth Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the fifth Se+1.70- site, Se+1.70- is bonded in a 4-coordinate geometry to three Nb5+ and one Fe2+ atom. In the sixth Se+1.70- site, Se+1.70- is bonded to three Nb5+ and one V4+ atom to form distorted corner-sharing SeNb3V tetrahedra. In the seventh Se+1.70- site, Se+1.70- is bonded to three Nb5+ and one V4+ atom to form distorted corner-sharing SeNb3V tetrahedra. In the eighth Se+1.70- site, Se+1.70- is bonded in a 4-coordinate geometry to three Nb5+ and one V4+ atom. In the ninth Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the tenth Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the eleventh Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the twelfth Se+1.70- site, Se+1.70- is bonded in a 2-coordinate geometry to two equivalent Nb5+ atoms. In the thirteenth Se+1.70- site, Se+1.70- is bonded in a distorted trigonal non-coplanar geometry to one Nb5+ and two equivalent Fe2+ atoms. In the fourteenth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent V4+ atoms. In the fifteenth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to one Nb5+ and two equivalent V4+ atoms. In the sixteenth Se+1.70- site, Se+1.70- is bonded in a distorted trigonal non-coplanar geometry to one Nb5+ and two equivalent V4+ atoms. In the seventeenth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to one V4+ and two equivalent Fe2+ atoms. In the eighteenth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to three V4+ atoms. In the nineteenth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to three V4+ atoms. In the twentieth Se+1.70- site, Se+1.70- is bonded in a 3-coordinate geometry to two equivalent V4+ and one Fe2+ atom.

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2020-06-04. Materials Data on Nb4V3FeSe20 by Materials Project. https://doi.org/10.17188/1712021

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36 MATERIALS SCIENCE↗