FeAsS is Hausmannite-derived structured and crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to three equivalent As(1) and three equivalent S(1) atoms to form distorted FeAs3S3 octahedra that share corners with eight equivalent Fe(1)As3S3 octahedra, corners with three equivalent As(1)Fe3S tetrahedra, corners with three equivalent S(1)Fe3As tetrahedra, and edges with two equivalent Fe(1)As3S3 octahedra. The corner-sharing octahedral tilt angles range from 53-62°. As(1) is bonded to three equivalent Fe(1) and one S(1) atom to form AsFe3S tetrahedra that share corners with three equivalent Fe(1)As3S3 octahedra, corners with four equivalent As(1)Fe3S tetrahedra, corners with nine equivalent S(1)Fe3As tetrahedra, and  an edgeedge with one As(1)Fe3S tetrahedra. The corner-sharing octahedral tilt angles range from 69-74°. S(1) is bonded to three equivalent Fe(1) and one As(1) atom to form SFe3As tetrahedra that share corners with three equivalent Fe(1)As3S3 octahedra, corners with four equivalent S(1)Fe3As tetrahedra, corners with nine equivalent As(1)Fe3S tetrahedra, and  an edgeedge with one S(1)Fe3As tetrahedra. The corner-sharing octahedral tilt angles range from 76-77°.
FeAsS is Hausmannite-derived structured and crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to three equivalent As(1) and three equivalent S(1) atoms to form distorted FeAs3S3 octahedra that share corners with eight equivalent Fe(1)As3S3 octahedra, corners with three equivalent As(1)Fe3S tetrahedra, corners with three equivalent S(1)Fe3As tetrahedra, and edges with two equivalent Fe(1)As3S3 octahedra. The corner-sharing octahedral tilt angles range from 53-62°. There are a spread of Fe(1)-As(1) bond distances ranging from 2.37-2.40 Å. There are a spread of Fe(1)-S(1) bond distances ranging from 2.18-2.21 Å. As(1) is bonded to three equivalent Fe(1) and one S(1) atom to form AsFe3S tetrahedra that share corners with three equivalent Fe(1)As3S3 octahedra, corners with four equivalent As(1)Fe3S tetrahedra, corners with nine equivalent S(1)Fe3As tetrahedra, and  an edgeedge with one As(1)Fe3S tetrahedra. The corner-sharing octahedral tilt angles range from 69-74°. The As(1)-S(1) bond length is 2.37 Å. S(1) is bonded to three equivalent Fe(1) and one As(1) atom to form SFe3As tetrahedra that share corners with three equivalent Fe(1)As3S3 octahedra, corners with four equivalent S(1)Fe3As tetrahedra, corners with nine equivalent As(1)Fe3S tetrahedra, and  an edgeedge with one S(1)Fe3As tetrahedra. The corner-sharing octahedral tilt angles range from 76-77°.