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DOE OSTI · 1276598

Materials Data on K2NbS7 by Materials Project

Abstract

K2NbS7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 9-coordinate geometry to nine S+0.86- atoms. There are a spread of K–S bond distances ranging from 3.18–3.67 Å. In the second K1+ site, K1+ is bonded in a 10-coordinate geometry to ten S+0.86- atoms. There are a spread of K–S bond distances ranging from 3.29–3.74 Å. In the third K1+ site, K1+ is bonded in a 10-coordinate geometry to ten S+0.86- atoms. There are a spread of K–S bond distances ranging from 3.29–3.92 Å. In the fourth K1+ site, K1+ is bonded in a 5-coordinate geometry to five S+0.86- atoms. There are a spread of K–S bond distances ranging from 3.25–3.39 Å. There are two inequivalent Nb4+ sites. In the first Nb4+ site, Nb4+ is bonded in a 7-coordinate geometry to seven S+0.86- atoms. There are a spread of Nb–S bond distances ranging from 2.22–2.98 Å. In the second Nb4+ site, Nb4+ is bonded in a 7-coordinate geometry to seven S+0.86- atoms. There are a spread of Nb–S bond distances ranging from 2.24–2.99 Å. There are fourteen inequivalent S+0.86- sites. In the first S+0.86- site, S+0.86- is bonded in a 1-coordinate geometry to two K1+, two Nb4+, and one S+0.86- atom. The S–S bond length is 2.09 Å. In the second S+0.86- site, S+0.86- is bonded in a 5-coordinate geometry to two K1+, two Nb4+, and one S+0.86- atom. The S–S bond length is 2.08 Å. In the third S+0.86- site, S+0.86- is bonded in a 5-coordinate geometry to three K1+, one Nb4+, and one S+0.86- atom. The S–S bond length is 2.08 Å. In the fourth S+0.86- site, S+0.86- is bonded in a 1-coordinate geometry to two K1+ and two Nb4+ atoms. In the fifth S+0.86- site, S+0.86- is bonded in a 1-coordinate geometry to three K1+, one Nb4+, and one S+0.86- atom. In the sixth S+0.86- site, S+0.86- is bonded in a 4-coordinate geometry to two K1+, one Nb4+, and one S+0.86- atom. In the seventh S+0.86- site, S+0.86- is bonded in a distorted single-bond geometry to two K1+ and one Nb4+ atom. In the eighth S+0.86- site, S+0.86- is bonded in a 1-coordinate geometry to three K1+, one Nb4+, and one S+0.86- atom. In the ninth S+0.86- site, S+0.86- is bonded in a 1-coordinate geometry to three K1+ and one Nb4+ atom. In the tenth S+0.86- site, S+0.86- is bonded in a 4-coordinate geometry to two K1+, one Nb4+, and one S+0.86- atom. The S–S bond length is 2.09 Å. In the eleventh S+0.86- site, S+0.86- is bonded in a distorted trigonal non-coplanar geometry to one K1+ and two S+0.86- atoms. The S–S bond length is 2.07 Å. In the twelfth S+0.86- site, S+0.86- is bonded in a distorted single-bond geometry to four K1+ and one Nb4+ atom. In the thirteenth S+0.86- site, S+0.86- is bonded in a 3-coordinate geometry to one K1+ and two S+0.86- atoms. The S–S bond length is 2.06 Å. In the fourteenth S+0.86- site, S+0.86- is bonded to four K1+ and one S+0.86- atom to form a mixture of distorted corner and edge-sharing SK4S trigonal bipyramids.

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2020-05-30. Materials Data on K2NbS7 by Materials Project. https://doi.org/10.17188/1276598

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