Materials Data on FeCu2GeS4 by Materials Project

Cu2FeGeS4 is Stannite-like structured and crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. Fe2+ is bonded to four equivalent S2- atoms to form FeS4 tetrahedra that share corners with four equivalent GeS4 tetrahedra and corners with eight CuS4 tetrahedra. All Fe–S bond lengths are 2.28 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with four equivalent CuS4 tetrahedra, and corners with four equivalent GeS4 tetrahedra. All Cu–S bond lengths are 2.30 Å. In the second Cu1+ site, Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra, corners with four equivalent CuS4 tetrahedra, and corners with four equivalent GeS4 tetrahedra. All Cu–S bond lengths are 2.31 Å. Ge4+ is bonded to four equivalent S2- atoms to form GeS4 tetrahedra that share corners with four equivalent FeS4 tetrahedra and corners with eight CuS4 tetrahedra. All Ge–S bond lengths are 2.30 Å. S2- is bonded to one Fe2+, two Cu1+, and one Ge4+ atom to form corner-sharing SFeCu2Ge tetrahedra.