Ti2FeS4 crystallizes in the monoclinic C2/m space group. Ti(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form TiS6 octahedra that share corners with six equivalent Fe(1)S6 octahedra, edges with six equivalent Ti(1)S6 octahedra, and  a faceface with one Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. Fe(1) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form FeS6 octahedra that share corners with twelve equivalent Ti(1)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and faces with two equivalent Ti(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. There are two inequivalent S sites. In the first S site, S(2) is bonded to three equivalent Ti(1) and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing STi3Fe2 square pyramids. In the second S site, S(1) is bonded in a rectangular see-saw-like geometry to three equivalent Ti(1) and one Fe(1) atom.
Ti2FeS4 crystallizes in the monoclinic C2/m space group. Ti(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form TiS6 octahedra that share corners with six equivalent Fe(1)S6 octahedra, edges with six equivalent Ti(1)S6 octahedra, and  a faceface with one Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. There are two shorter (2.42 Å) and one longer (2.44 Å) Ti(1)-S(1) bond length. There is one shorter (2.47 Å) and two longer (2.48 Å) Ti(1)-S(2) bond lengths. Fe(1) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form FeS6 octahedra that share corners with twelve equivalent Ti(1)S6 octahedra, edges with two equivalent Fe(1)S6 octahedra, and faces with two equivalent Ti(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. Both Fe(1)-S(1) bond lengths are 2.34 Å. All Fe(1)-S(2) bond lengths are 2.42 Å. There are two inequivalent S sites. In the first S site, S(2) is bonded to three equivalent Ti(1) and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing STi3Fe2 square pyramids. In the second S site, S(1) is bonded in a rectangular see-saw-like geometry to three equivalent Ti(1) and one Fe(1) atom.