Materials Data on La3Fe2S7 by Materials Project
La3Fe2S7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. La3+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.89–3.49 Å. There are two inequivalent Fe+2.50+ sites. In the first Fe+2.50+ site, Fe+2.50+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.23 Å) and three longer (2.26 Å) Fe–S bond lengths. In the second Fe+2.50+ site, Fe+2.50+ is bonded to six equivalent S2- atoms to form face-sharing FeS6 octahedra. There are three shorter (2.39 Å) and three longer (2.42 Å) Fe–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent La3+ and one Fe+2.50+ atom. In the second S2- site, S2- is bonded in a tetrahedral geometry to three equivalent La3+ and one Fe+2.50+ atom. In the third S2- site, S2- is bonded in a 5-coordinate geometry to four equivalent La3+ and two equivalent Fe+2.50+ atoms.