Li2Fe2S3 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted LiS4 trigonal pyramids that share corners with six equivalent Fe(1)S4 tetrahedra, corners with six equivalent Li(1)S4 trigonal pyramids, edges with two equivalent Fe(1)S4 tetrahedra, and  an edgeedge with one Li(1)S4 trigonal pyramid. Fe(1) is bonded to one S(1) and three equivalent S(2) atoms to form distorted FeS4 tetrahedra that share corners with five equivalent Fe(1)S4 tetrahedra, corners with six equivalent Li(1)S4 trigonal pyramids,  an edgeedge with one Fe(1)S4 tetrahedra, and edges with two equivalent Li(1)S4 trigonal pyramids. There are two inequivalent S sites. In the first S site, S(1) is bonded to four equivalent Li(1) and two equivalent Fe(1) atoms to form corner-sharing SLi4Fe2 octahedra. The corner-sharing octahedral tilt angles are 44°. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to two equivalent Li(1) and three equivalent Fe(1) atoms.
Li2Fe2S3 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted LiS4 trigonal pyramids that share corners with six equivalent Fe(1)S4 tetrahedra, corners with six equivalent Li(1)S4 trigonal pyramids, edges with two equivalent Fe(1)S4 tetrahedra, and  an edgeedge with one Li(1)S4 trigonal pyramid. There is one shorter (2.47 Å) and one longer (2.48 Å) Li(1)-S(1) bond length. There is one shorter (2.47 Å) and one longer (2.62 Å) Li(1)-S(2) bond length. Fe(1) is bonded to one S(1) and three equivalent S(2) atoms to form distorted FeS4 tetrahedra that share corners with five equivalent Fe(1)S4 tetrahedra, corners with six equivalent Li(1)S4 trigonal pyramids,  an edgeedge with one Fe(1)S4 tetrahedra, and edges with two equivalent Li(1)S4 trigonal pyramids. The Fe(1)-S(1) bond length is 2.31 Å. There are a spread of Fe(1)-S(2) bond distances ranging from 2.31-2.37 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded to four equivalent Li(1) and two equivalent Fe(1) atoms to form corner-sharing SLi4Fe2 octahedra. The corner-sharing octahedral tilt angles are 44°. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to two equivalent Li(1) and three equivalent Fe(1) atoms.