Materials Data on Nb2Se9 by Materials Project
Nb2Se9 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one Nb2Se9 ribbon oriented in the (1, 1, 1) direction. there are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.11- atoms. There are a spread of Nb–Se bond distances ranging from 2.65–2.76 Å. In the second Nb5+ site, Nb5+ is bonded in a 8-coordinate geometry to eight Se+1.11- atoms. There are a spread of Nb–Se bond distances ranging from 2.65–2.76 Å. There are nine inequivalent Se+1.11- sites. In the first Se+1.11- site, Se+1.11- is bonded in a 1-coordinate geometry to one Nb5+ and one Se+1.11- atom. The Se–Se bond length is 2.40 Å. In the second Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and one Se+1.11- atom. The Se–Se bond length is 2.34 Å. In the third Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Nb5+ and one Se+1.11- atom. The Se–Se bond length is 2.40 Å. In the fourth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and one Se+1.11- atom. The Se–Se bond length is 2.34 Å. In the fifth Se+1.11- site, Se+1.11- is bonded in a distorted L-shaped geometry to two Nb5+ atoms. In the sixth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and one Se+1.11- atom. In the seventh Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two equivalent Nb5+ and one Se+1.11- atom. In the eighth Se+1.11- site, Se+1.11- is bonded in a 2-coordinate geometry to two Nb5+ and one Se+1.11- atom. In the ninth Se+1.11- site, Se+1.11- is bonded in a 1-coordinate geometry to one Nb5+ and one Se+1.11- atom.