Materials Data on Cs2FeF5 by Materials Project

Cs2FeF5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Cs–F bond distances ranging from 3.01–3.28 Å. In the second Cs1+ site, Cs1+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Cs–F bond distances ranging from 3.09–3.62 Å. Fe3+ is bonded to six F1- atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Fe–F bond distances ranging from 1.92–2.11 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to five Cs1+ and one Fe3+ atom. In the second F1- site, F1- is bonded in a distorted single-bond geometry to four Cs1+ and one Fe3+ atom. In the third F1- site, F1- is bonded in a linear geometry to four Cs1+ and two equivalent Fe3+ atoms. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to four Cs1+ and one Fe3+ atom.