Materials Data on Nb3Se12I by Materials Project
(NbSe4)3I crystallizes in the tetragonal P4/mnc space group. The structure is three-dimensional. there are two inequivalent Nb+4.33+ sites. In the first Nb+4.33+ site, Nb+4.33+ is bonded in a 8-coordinate geometry to eight Se1- atoms. There are four shorter (2.60 Å) and four longer (2.77 Å) Nb–Se bond lengths. In the second Nb+4.33+ site, Nb+4.33+ is bonded to eight Se1- atoms to form distorted face-sharing NbSe8 hexagonal bipyramids. There are a spread of Nb–Se bond distances ranging from 2.66–2.75 Å. There are four inequivalent Se1- sites. In the first Se1- site, Se1- is bonded in a 2-coordinate geometry to two Nb+4.33+ atoms. In the second Se1- site, Se1- is bonded in a 2-coordinate geometry to two equivalent Nb+4.33+ and one Se1- atom. The Se–Se bond length is 2.36 Å. In the third Se1- site, Se1- is bonded in a 2-coordinate geometry to two equivalent Nb+4.33+, one Se1-, and two equivalent I1- atoms. Both Se–I bond lengths are 4.06 Å. In the fourth Se1- site, Se1- is bonded in a 2-coordinate geometry to two Nb+4.33+ and one I1- atom. The Se–I bond length is 3.39 Å. I1- is bonded in a 4-coordinate geometry to eight Se1- atoms.