Materials Data on NaFeBr4 by Materials Project

Abstract

NaFeBr4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Na1+ is bonded to six Br1- atoms to form distorted NaBr6 pentagonal pyramids that share corners with four equivalent NaBr6 pentagonal pyramids, corners with two equivalent FeBr4 tetrahedra, and edges with two equivalent FeBr4 tetrahedra. There are a spread of Na–Br bond distances ranging from 3.01–3.22 Å. Fe3+ is bonded to four Br1- atoms to form FeBr4 tetrahedra that share corners with two equivalent NaBr6 pentagonal pyramids and edges with two equivalent NaBr6 pentagonal pyramids. There are a spread of Fe–Br bond distances ranging from 2.34–2.37 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in an L-shaped geometry to one Na1+ and one Fe3+ atom. In the second Br1- site, Br1- is bonded in a distorted T-shaped geometry to two equivalent Na1+ and one Fe3+ atom. In the third Br1- site, Br1- is bonded in an L-shaped geometry to one Na1+ and one Fe3+ atom.