Fe3S is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. Fe(1) is bonded to eight equivalent Fe(1) and four equivalent S(1) atoms to form distorted FeFe8S4 cuboctahedra that share corners with four equivalent S(1)Fe12 cuboctahedra, corners with fourteen equivalent Fe(1)Fe8S4 cuboctahedra, edges with six equivalent S(1)Fe12 cuboctahedra, edges with twelve equivalent Fe(1)Fe8S4 cuboctahedra, faces with four equivalent S(1)Fe12 cuboctahedra, and faces with sixteen equivalent Fe(1)Fe8S4 cuboctahedra. S(1) is bonded to twelve equivalent Fe(1) atoms to form SFe12 cuboctahedra that share corners with six equivalent S(1)Fe12 cuboctahedra, corners with twelve equivalent Fe(1)Fe8S4 cuboctahedra, edges with eighteen equivalent Fe(1)Fe8S4 cuboctahedra, faces with eight equivalent S(1)Fe12 cuboctahedra, and faces with twelve equivalent Fe(1)Fe8S4 cuboctahedra.
Fe3S is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. Fe(1) is bonded to eight equivalent Fe(1) and four equivalent S(1) atoms to form distorted FeFe8S4 cuboctahedra that share corners with four equivalent S(1)Fe12 cuboctahedra, corners with fourteen equivalent Fe(1)Fe8S4 cuboctahedra, edges with six equivalent S(1)Fe12 cuboctahedra, edges with twelve equivalent Fe(1)Fe8S4 cuboctahedra, faces with four equivalent S(1)Fe12 cuboctahedra, and faces with sixteen equivalent Fe(1)Fe8S4 cuboctahedra. There are a spread of Fe(1)-Fe(1) bond distances ranging from 2.51-2.66 Å. There are two shorter (2.58 Å) and two longer (2.62 Å) Fe(1)-S(1) bond lengths. S(1) is bonded to twelve equivalent Fe(1) atoms to form SFe12 cuboctahedra that share corners with six equivalent S(1)Fe12 cuboctahedra, corners with twelve equivalent Fe(1)Fe8S4 cuboctahedra, edges with eighteen equivalent Fe(1)Fe8S4 cuboctahedra, faces with eight equivalent S(1)Fe12 cuboctahedra, and faces with twelve equivalent Fe(1)Fe8S4 cuboctahedra.