Materials Data on Fe7S8 by Materials Project

Fe7S8 crystallizes in the trigonal P3_121 space group. The structure is three-dimensional. there are five inequivalent Fe+2.29+ sites. In the first Fe+2.29+ site, Fe+2.29+ is bonded in a 5-coordinate geometry to five S2- atoms. There are a spread of Fe–S bond distances ranging from 2.10–2.31 Å. In the second Fe+2.29+ site, Fe+2.29+ is bonded to six S2- atoms to form a mixture of distorted corner, edge, and face-sharing FeS6 octahedra. The corner-sharing octahedra tilt angles range from 50–51°. There are a spread of Fe–S bond distances ranging from 2.18–2.37 Å. In the third Fe+2.29+ site, Fe+2.29+ is bonded to six S2- atoms to form a mixture of corner, edge, and face-sharing FeS6 octahedra. The corner-sharing octahedra tilt angles range from 44–60°. There are a spread of Fe–S bond distances ranging from 2.19–2.40 Å. In the fourth Fe+2.29+ site, Fe+2.29+ is bonded to six S2- atoms to form a mixture of corner, edge, and face-sharing FeS6 octahedra. The corner-sharing octahedra tilt angles range from 50–60°. There are a spread of Fe–S bond distances ranging from 2.20–2.41 Å. In the fifth Fe+2.29+ site, Fe+2.29+ is bonded to six S2- atoms to form a mixture of corner, edge, and face-sharing FeS6 octahedra. The corner-sharing octahedra tilt angles range from 44–60°. There are a spread of Fe–S bond distances ranging from 2.24–2.49 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to five Fe+2.29+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to five Fe+2.29+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to five Fe+2.29+ atoms. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to five Fe+2.29+ atoms.