Materials Data on Fe3(Se2S)2 by Materials Project
Fe3(Se2S)2 is Marcasite-derived structured and crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are six inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to five Se+0.50- and one S2- atom to form FeSe5S octahedra that share corners with eight FeSe4S2 octahedra and edges with two equivalent FeSe5S octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are four shorter (2.35 Å) and one longer (2.37 Å) Fe–Se bond lengths. The Fe–S bond length is 2.26 Å. In the second Fe2+ site, Fe2+ is bonded to four Se+0.50- and two S2- atoms to form a mixture of corner and edge-sharing FeSe4S2 octahedra. The corner-sharing octahedra tilt angles range from 56–58°. There are two shorter (2.34 Å) and two longer (2.35 Å) Fe–Se bond lengths. There are one shorter (2.28 Å) and one longer (2.29 Å) Fe–S bond lengths. In the third Fe2+ site, Fe2+ is bonded to five Se+0.50- and one S2- atom to form FeSe5S octahedra that share corners with eight FeSe4S2 octahedra and edges with two equivalent FeSe5S octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Fe–Se bond distances ranging from 2.34–2.36 Å. The Fe–S bond length is 2.23 Å. In the fourth Fe2+ site, Fe2+ is bonded to four Se+0.50- and two equivalent S2- atoms to form FeSe4S2 octahedra that share corners with eight FeSe5S octahedra and edges with two equivalent FeSe4S2 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are a spread of Fe–Se bond distances ranging from 2.33–2.37 Å. Both Fe–S bond lengths are 2.29 Å. In the fifth Fe2+ site, Fe2+ is bonded to four Se+0.50- and two equivalent S2- atoms to form FeSe4S2 octahedra that share corners with eight FeSe5S octahedra and edges with two equivalent FeSe4S2 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Fe–Se bond distances ranging from 2.33–2.37 Å. Both Fe–S bond lengths are 2.28 Å. In the sixth Fe2+ site, Fe2+ is bonded to two Se+0.50- and four S2- atoms to form FeSe2S4 octahedra that share corners with eight FeSe5S octahedra and edges with two equivalent FeSe2S4 octahedra. The corner-sharing octahedra tilt angles range from 56–58°. There are one shorter (2.33 Å) and one longer (2.35 Å) Fe–Se bond lengths. There are two shorter (2.30 Å) and two longer (2.31 Å) Fe–S bond lengths. There are eight inequivalent Se+0.50- sites. In the first Se+0.50- site, Se+0.50- is bonded in a 4-coordinate geometry to three Fe2+ atoms. In the second Se+0.50- site, Se+0.50- is bonded in a 4-coordinate geometry to three Fe2+ and one S2- atom. The Se–S bond length is 2.55 Å. In the third Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the fourth Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the fifth Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the sixth Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the seventh Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the eighth Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three Fe2+ atoms. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Fe2+ and one Se+0.50- atom. In the second S2- site, S2- is bonded in a distorted trigonal planar geometry to three Fe2+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to three Fe2+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to three Fe2+ atoms.