Ti5CuSb3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 8-coordinate geometry to two equivalent Ti(1) and six equivalent Sb(1) atoms. In the second Ti site, Ti(2) is bonded to two equivalent Cu(1) and five equivalent Sb(1) atoms to form a mixture of distorted face, corner, and edge-sharing TiCu2Sb5 pentagonal bipyramids. Cu(1) is bonded to six equivalent Ti(2) atoms to form distorted face-sharing CuTi6 octahedra. Sb(1) is bonded in a 9-coordinate geometry to four equivalent Ti(1) and five equivalent Ti(2) atoms.
Ti5CuSb3 crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 8-coordinate geometry to two equivalent Ti(1) and six equivalent Sb(1) atoms. Both Ti(1)-Ti(1) bond lengths are 2.74 Å. All Ti(1)-Sb(1) bond lengths are 2.88 Å. In the second Ti site, Ti(2) is bonded to two equivalent Cu(1) and five equivalent Sb(1) atoms to form a mixture of distorted face, corner, and edge-sharing TiCu2Sb5 pentagonal bipyramids. Both Ti(2)-Cu(1) bond lengths are 2.57 Å. There are a spread of Ti(2)-Sb(1) bond distances ranging from 2.78-2.90 Å. Cu(1) is bonded to six equivalent Ti(2) atoms to form distorted face-sharing CuTi6 octahedra. Sb(1) is bonded in a 9-coordinate geometry to four equivalent Ti(1) and five equivalent Ti(2) atoms.