La2CuS4 is (La,Ba)CuO4 structured and crystallizes in the orthorhombic Fmmm space group. La(1) is bonded in a 9-coordinate geometry to four equivalent S(1) and five equivalent S(2) atoms. Cu(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form corner-sharing CuS6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent S sites. In the first S site, S(1) is bonded to four equivalent La(1) and two equivalent Cu(1) atoms to form SLa4Cu2 octahedra that share corners with two equivalent S(1)La4Cu2 octahedra, corners with twelve equivalent S(2)La5Cu octahedra, edges with two equivalent S(1)La4Cu2 octahedra, faces with four equivalent S(1)La4Cu2 octahedra, and faces with four equivalent S(2)La5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-49°. In the second S site, S(2) is bonded to five equivalent La(1) and one Cu(1) atom to form distorted SLa5Cu octahedra that share corners with five equivalent S(2)La5Cu octahedra, corners with twelve equivalent S(1)La4Cu2 octahedra, edges with eight equivalent S(2)La5Cu octahedra, and faces with four equivalent S(1)La4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-49°.
La2CuS4 is (La,Ba)CuO4 structured and crystallizes in the orthorhombic Fmmm space group. La(1) is bonded in a 9-coordinate geometry to four equivalent S(1) and five equivalent S(2) atoms. All La(1)-S(1) bond lengths are 3.06 Å. There are a spread of La(1)-S(2) bond distances ranging from 2.84-3.24 Å. Cu(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form corner-sharing CuS6 octahedra. The corner-sharing octahedra are not tilted. Both Cu(1)-S(2) bond lengths are 2.81 Å. All Cu(1)-S(1) bond lengths are 2.22 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded to four equivalent La(1) and two equivalent Cu(1) atoms to form SLa4Cu2 octahedra that share corners with two equivalent S(1)La4Cu2 octahedra, corners with twelve equivalent S(2)La5Cu octahedra, edges with two equivalent S(1)La4Cu2 octahedra, faces with four equivalent S(1)La4Cu2 octahedra, and faces with four equivalent S(2)La5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-49°. In the second S site, S(2) is bonded to five equivalent La(1) and one Cu(1) atom to form distorted SLa5Cu octahedra that share corners with five equivalent S(2)La5Cu octahedra, corners with twelve equivalent S(1)La4Cu2 octahedra, edges with eight equivalent S(2)La5Cu octahedra, and faces with four equivalent S(1)La4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-49°.