SmCu9In2 crystallizes in the tetragonal P4/mbm space group. Sm(1) is bonded in a 20-coordinate geometry to eight equivalent Cu(2), eight equivalent Cu(3), and four equivalent In(1) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Cu(2), four equivalent Cu(3), and four equivalent In(1) atoms to form CuIn4Cu8 cuboctahedra that share corners with four equivalent Cu(3)Sm2In3Cu7 cuboctahedra, corners with twelve equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with two equivalent Cu(1)In4Cu8 cuboctahedra, faces with eight equivalent Cu(2)Sm2In2Cu8 cuboctahedra, and faces with twelve equivalent Cu(3)Sm2In3Cu7 cuboctahedra. In the second Cu site, Cu(2) is bonded to two equivalent Sm(1), one Cu(1), three equivalent Cu(2), four equivalent Cu(3), and two equivalent In(1) atoms to form distorted CuSm2In2Cu8 cuboctahedra that share corners with three equivalent Cu(1)In4Cu8 cuboctahedra, corners with six equivalent Cu(3)Sm2In3Cu7 cuboctahedra, corners with eleven equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with two equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with four equivalent Cu(3)Sm2In3Cu7 cuboctahedra, faces with two equivalent Cu(1)In4Cu8 cuboctahedra, faces with seven equivalent Cu(2)Sm2In2Cu8 cuboctahedra, and faces with ten equivalent Cu(3)Sm2In3Cu7 cuboctahedra. In the third Cu site, Cu(3) is bonded to two equivalent Sm(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), and three equivalent In(1) atoms to form CuSm2In3Cu7 cuboctahedra that share  a cornercorner with one Cu(1)In4Cu8 cuboctahedra, corners with six equivalent Cu(2)Sm2In2Cu8 cuboctahedra, corners with eleven equivalent Cu(3)Sm2In3Cu7 cuboctahedra, edges with four equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with five equivalent Cu(3)Sm2In3Cu7 cuboctahedra, faces with three equivalent Cu(1)In4Cu8 cuboctahedra, faces with seven equivalent Cu(3)Sm2In3Cu7 cuboctahedra, and faces with ten equivalent Cu(2)Sm2In2Cu8 cuboctahedra. In(1) is bonded in a 15-coordinate geometry to two equivalent Sm(1), two equivalent Cu(1), four equivalent Cu(2), six equivalent Cu(3), and one In(1) atom.
SmCu9In2 crystallizes in the tetragonal P4/mbm space group. Sm(1) is bonded in a 20-coordinate geometry to eight equivalent Cu(2), eight equivalent Cu(3), and four equivalent In(1) atoms. All Sm(1)-Cu(2) bond lengths are 3.10 Å. All Sm(1)-Cu(3) bond lengths are 3.36 Å. All Sm(1)-In(1) bond lengths are 3.36 Å. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Cu(2), four equivalent Cu(3), and four equivalent In(1) atoms to form CuIn4Cu8 cuboctahedra that share corners with four equivalent Cu(3)Sm2In3Cu7 cuboctahedra, corners with twelve equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with two equivalent Cu(1)In4Cu8 cuboctahedra, faces with eight equivalent Cu(2)Sm2In2Cu8 cuboctahedra, and faces with twelve equivalent Cu(3)Sm2In3Cu7 cuboctahedra. All Cu(1)-Cu(2) bond lengths are 2.55 Å. All Cu(1)-Cu(3) bond lengths are 2.47 Å. All Cu(1)-In(1) bond lengths are 2.91 Å. In the second Cu site, Cu(2) is bonded to two equivalent Sm(1), one Cu(1), three equivalent Cu(2), four equivalent Cu(3), and two equivalent In(1) atoms to form distorted CuSm2In2Cu8 cuboctahedra that share corners with three equivalent Cu(1)In4Cu8 cuboctahedra, corners with six equivalent Cu(3)Sm2In3Cu7 cuboctahedra, corners with eleven equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with two equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with four equivalent Cu(3)Sm2In3Cu7 cuboctahedra, faces with two equivalent Cu(1)In4Cu8 cuboctahedra, faces with seven equivalent Cu(2)Sm2In2Cu8 cuboctahedra, and faces with ten equivalent Cu(3)Sm2In3Cu7 cuboctahedra. There are two shorter (2.58 Å) and one longer (2.77 Å) Cu(2)-Cu(2) bond length. There are two shorter (2.56 Å) and two longer (2.60 Å) Cu(2)-Cu(3) bond lengths. Both Cu(2)-In(1) bond lengths are 2.94 Å. In the third Cu site, Cu(3) is bonded to two equivalent Sm(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), and three equivalent In(1) atoms to form CuSm2In3Cu7 cuboctahedra that share  a cornercorner with one Cu(1)In4Cu8 cuboctahedra, corners with six equivalent Cu(2)Sm2In2Cu8 cuboctahedra, corners with eleven equivalent Cu(3)Sm2In3Cu7 cuboctahedra, edges with four equivalent Cu(2)Sm2In2Cu8 cuboctahedra, edges with five equivalent Cu(3)Sm2In3Cu7 cuboctahedra, faces with three equivalent Cu(1)In4Cu8 cuboctahedra, faces with seven equivalent Cu(3)Sm2In3Cu7 cuboctahedra, and faces with ten equivalent Cu(2)Sm2In2Cu8 cuboctahedra. There is one shorter (2.47 Å) and one longer (2.55 Å) Cu(3)-Cu(3) bond length. There is one shorter (2.70 Å) and two longer (2.86 Å) Cu(3)-In(1) bond lengths. In(1) is bonded in a 15-coordinate geometry to two equivalent Sm(1), two equivalent Cu(1), four equivalent Cu(2), six equivalent Cu(3), and one In(1) atom. The In(1)-In(1) bond length is 2.95 Å.