Materials Data on FeCu3S8 by Materials Project
FeCu3S8 is Pyrite-derived structured and crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Fe3+ is bonded to six equivalent S1- atoms to form FeS6 octahedra that share corners with twelve equivalent CuS6 octahedra and corners with six equivalent SFeCu2S tetrahedra. The corner-sharing octahedra tilt angles range from 64–65°. All Fe–S bond lengths are 2.30 Å. Cu+1.67+ is bonded to six S1- atoms to form CuS6 octahedra that share corners with four equivalent FeS6 octahedra, corners with eight equivalent CuS6 octahedra, and corners with six SFeCu2S tetrahedra. The corner-sharing octahedra tilt angles range from 64–69°. There are a spread of Cu–S bond distances ranging from 2.40–2.47 Å. There are two inequivalent S1- sites. In the first S1- site, S1- is bonded to one Fe3+, two equivalent Cu+1.67+, and one S1- atom to form distorted SFeCu2S tetrahedra that share a cornercorner with one FeS6 octahedra, corners with two equivalent CuS6 octahedra, and corners with fifteen SFeCu2S tetrahedra. The corner-sharing octahedra tilt angles range from 69–80°. The S–S bond length is 2.09 Å. In the second S1- site, S1- is bonded to three equivalent Cu+1.67+ and one S1- atom to form distorted SCu3S tetrahedra that share corners with three equivalent CuS6 octahedra and corners with fifteen SFeCu2S tetrahedra. The corner-sharing octahedral tilt angles are 74°. The S–S bond length is 2.02 Å.