Cd3(CuP5)2 crystallizes in the trigonal R3m space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one P(4) and three equivalent P(3) atoms to form CuP4 tetrahedra that share corners with six equivalent P(2)Cd2P2 tetrahedra and corners with six equivalent P(1)CdCuP2 tetrahedra. In the second Cu site, Cu(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent P(1) atoms. Cd(1) is bonded in a 3-coordinate geometry to one P(1) and two equivalent P(2) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Cu(2), one Cd(1), and two equivalent P(3) atoms to form PCdCuP2 tetrahedra that share corners with two equivalent Cu(1)P4 tetrahedra, corners with four equivalent P(2)Cd2P2 tetrahedra, and corners with four equivalent P(1)CdCuP2 tetrahedra. In the second P site, P(2) is bonded to two equivalent Cd(1), one P(3), and one P(4) atom to form PCd2P2 tetrahedra that share corners with two equivalent Cu(1)P4 tetrahedra, corners with four equivalent P(2)Cd2P2 tetrahedra, and corners with four equivalent P(1)CdCuP2 tetrahedra. In the third P site, P(3) is bonded to one Cu(1), one P(2), and two equivalent P(1) atoms to form corner-sharing PCuP3 tetrahedra. In the fourth P site, P(4) is bonded to one Cu(1) and three equivalent P(2) atoms to form corner-sharing PCuP3 tetrahedra.
Cd3(CuP5)2 crystallizes in the trigonal R3m space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one P(4) and three equivalent P(3) atoms to form CuP4 tetrahedra that share corners with six equivalent P(2)Cd2P2 tetrahedra and corners with six equivalent P(1)CdCuP2 tetrahedra. The Cu(1)-P(4) bond length is 2.33 Å. All Cu(1)-P(3) bond lengths are 2.33 Å. In the second Cu site, Cu(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent P(1) atoms. All Cu(2)-P(1) bond lengths are 2.30 Å. Cd(1) is bonded in a 3-coordinate geometry to one P(1) and two equivalent P(2) atoms. The Cd(1)-P(1) bond length is 2.65 Å. Both Cd(1)-P(2) bond lengths are 2.56 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one Cu(2), one Cd(1), and two equivalent P(3) atoms to form PCdCuP2 tetrahedra that share corners with two equivalent Cu(1)P4 tetrahedra, corners with four equivalent P(2)Cd2P2 tetrahedra, and corners with four equivalent P(1)CdCuP2 tetrahedra. Both P(1)-P(3) bond lengths are 2.21 Å. In the second P site, P(2) is bonded to two equivalent Cd(1), one P(3), and one P(4) atom to form PCd2P2 tetrahedra that share corners with two equivalent Cu(1)P4 tetrahedra, corners with four equivalent P(2)Cd2P2 tetrahedra, and corners with four equivalent P(1)CdCuP2 tetrahedra. The P(2)-P(3) bond length is 2.18 Å. The P(2)-P(4) bond length is 2.18 Å. In the third P site, P(3) is bonded to one Cu(1), one P(2), and two equivalent P(1) atoms to form corner-sharing PCuP3 tetrahedra. In the fourth P site, P(4) is bonded to one Cu(1) and three equivalent P(2) atoms to form corner-sharing PCuP3 tetrahedra.