Materials Data on KFeBr3 by Materials Project
KFeBr3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are a spread of K–Br bond distances ranging from 3.42–3.51 Å. Fe2+ is bonded to six Br1- atoms to form edge-sharing FeBr6 octahedra. There are a spread of Fe–Br bond distances ranging from 2.51–2.76 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 1-coordinate geometry to four equivalent K1+ and one Fe2+ atom. In the second Br1- site, Br1- is bonded in a 5-coordinate geometry to three equivalent K1+ and two equivalent Fe2+ atoms. In the third Br1- site, Br1- is bonded in a distorted rectangular see-saw-like geometry to one K1+ and three equivalent Fe2+ atoms.