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Materials Data on Nb2Tl4Se11 by Materials Project

Nb2Tl4Se11 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to seven Se+1.27- atoms to form distorted face-sharing NbSe7 pentagonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.48–2.88 Å. In the second Nb5+ site, Nb5+ is bonded to seven Se+1.27- atoms to form distorted face-sharing NbSe7 pentagonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.45–2.91 Å. There are four inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 7-coordinate geometry to ten Se+1.27- atoms. There are a spread of Tl–Se bond distances ranging from 3.22–4.03 Å. In the second Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to eight Se+1.27- atoms. There are a spread of Tl–Se bond distances ranging from 3.09–4.02 Å. In the third Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to six Se+1.27- atoms. There are a spread of Tl–Se bond distances ranging from 3.16–3.47 Å. In the fourth Tl1+ site, Tl1+ is bonded in a 9-coordinate geometry to nine Se+1.27- atoms. There are a spread of Tl–Se bond distances ranging from 3.12–3.92 Å. There are eleven inequivalent Se+1.27- sites. In the first Se+1.27- site, Se+1.27- is bonded in a 5-coordinate geometry to one Nb5+ and four Tl1+ atoms. In the second Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+ and three Tl1+ atoms. In the third Se+1.27- site, Se+1.27- is bonded in a 5-coordinate geometry to one Nb5+, three Tl1+, and one Se+1.27- atom. The Se–Se bond length is 2.39 Å. In the fourth Se+1.27- site, Se+1.27- is bonded in a 5-coordinate geometry to two Nb5+, two equivalent Tl1+, and one Se+1.27- atom. The Se–Se bond length is 2.41 Å. In the fifth Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+, three Tl1+, and one Se+1.27- atom. The Se–Se bond length is 2.39 Å. In the sixth Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+, two Tl1+, and one Se+1.27- atom. In the seventh Se+1.27- site, Se+1.27- is bonded in a 2-coordinate geometry to two Nb5+, three Tl1+, and one Se+1.27- atom. In the eighth Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+, three Tl1+, and one Se+1.27- atom. In the ninth Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+ and four Tl1+ atoms. In the tenth Se+1.27- site, Se+1.27- is bonded in a 1-coordinate geometry to one Nb5+ and four Tl1+ atoms. In the eleventh Se+1.27- site, Se+1.27- is bonded in a 4-coordinate geometry to two Nb5+ and two Tl1+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on NbTl3Se4 by Materials Project

NbTl3Se4 crystallizes in the cubic I-43m space group. The structure is three-dimensional and consists of two NbTl3Se4 frameworks. Nb5+ is bonded in a tetrahedral geometry to four equivalent Se2- atoms. All Nb–Se bond lengths are 2.42 Å. Tl1+ is bonded in a 8-coordinate geometry to four equivalent Se2- atoms. All Tl–Se bond lengths are 3.30 Å. Se2- is bonded in a 1-coordinate geometry to one Nb5+ and three equivalent Tl1+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Nb6TlSe8 by Materials Project

Nb6TlSe8 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted corner, edge, and face-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.85 Å. Tl1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All Tl–Se bond lengths are 3.34 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six equivalent Nb+2.50+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to four equivalent Nb+2.50+ and one Tl1+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Nb9TlSe12 by Materials Project

Nb9TlSe12 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are three inequivalent Nb+2.56+ sites. In the first Nb+2.56+ site, Nb+2.56+ is bonded to six Se2- atoms to form a mixture of distorted face, edge, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.60–2.83 Å. In the second Nb+2.56+ site, Nb+2.56+ is bonded to six Se2- atoms to form a mixture of distorted face, edge, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.84 Å. In the third Nb+2.56+ site, Nb+2.56+ is bonded to six Se2- atoms to form a mixture of distorted face, edge, and corner-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.84 Å. There are two inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All Tl–Se bond lengths are 3.33 Å. In the second Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All Tl–Se bond lengths are 3.33 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four Nb+2.56+ and one Tl1+ atom. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to four Nb+2.56+ and one Tl1+ atom. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to four Nb+2.56+ atoms. In the fourth Se2- site, Se2- is bonded to six Nb+2.56+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids.

36 MATERIALS SCIENCE↗