Materials Data on RbNb4Br11 by Materials Project
RbNb4Br11 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. Rb1+ is bonded in a 12-coordinate geometry to ten Br1- atoms. There are a spread of Rb–Br bond distances ranging from 3.73–4.11 Å. There are two inequivalent Nb+2.50+ sites. In the first Nb+2.50+ site, Nb+2.50+ is bonded to six Br1- atoms to form a mixture of distorted face and edge-sharing NbBr6 octahedra. There are a spread of Nb–Br bond distances ranging from 2.58–2.81 Å. In the second Nb+2.50+ site, Nb+2.50+ is bonded to six Br1- atoms to form edge-sharing NbBr6 octahedra. There are a spread of Nb–Br bond distances ranging from 2.65–2.78 Å. There are five inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 3-coordinate geometry to three Nb+2.50+ atoms. In the second Br1- site, Br1- is bonded in a 3-coordinate geometry to one Rb1+ and two Nb+2.50+ atoms. In the third Br1- site, Br1- is bonded in a distorted water-like geometry to one Rb1+ and two equivalent Nb+2.50+ atoms. In the fourth Br1- site, Br1- is bonded in a 2-coordinate geometry to two equivalent Rb1+ and two equivalent Nb+2.50+ atoms. In the fifth Br1- site, Br1- is bonded in an L-shaped geometry to one Rb1+ and two equivalent Nb+2.50+ atoms.