Mg6CdSn crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Cd(1), and two equivalent Sn(1) atoms to form distorted MgMg8Cd2Sn2 cuboctahedra that share corners with four equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with four equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), two equivalent Cd(1), and two equivalent Sn(1) atoms. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Sn(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form distorted MgMg10Cd2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, and faces with six equivalent Sn(1)Mg10Cd2 cuboctahedra. Cd(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sn(1) atoms to form CdMg10Sn2 cuboctahedra that share corners with four equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with six equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra. Sn(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form SnMg10Cd2 cuboctahedra that share corners with four equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with six equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cd2 cuboctahedra.
Mg6CdSn crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Cd(1), and two equivalent Sn(1) atoms to form distorted MgMg8Cd2Sn2 cuboctahedra that share corners with four equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with four equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with ten equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.30 Å. Both Mg(1)-Mg(2) bond lengths are 3.12 Å. Both Mg(1)-Mg(3) bond lengths are 3.15 Å. Both Mg(1)-Mg(4) bond lengths are 3.16 Å. There is one shorter (3.18 Å) and one longer (3.19 Å) Mg(1)-Cd(1) bond length. There is one shorter (3.18 Å) and one longer (3.19 Å) Mg(1)-Sn(1) bond length. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), two equivalent Cd(1), and two equivalent Sn(1) atoms. There is one shorter (3.17 Å) and one longer (3.19 Å) Mg(2)-Mg(4) bond length. Both Mg(2)-Cd(1) bond lengths are 3.15 Å. Both Mg(2)-Sn(1) bond lengths are 3.18 Å. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Sn(1) atoms. Both Mg(3)-Mg(4) bond lengths are 3.30 Å. Both Mg(3)-Sn(1) bond lengths are 3.14 Å. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form distorted MgMg10Cd2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, and faces with six equivalent Sn(1)Mg10Cd2 cuboctahedra. Both Mg(4)-Cd(1) bond lengths are 3.12 Å. Cd(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sn(1) atoms to form CdMg10Sn2 cuboctahedra that share corners with four equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with six equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Sn(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, and faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra. Both Cd(1)-Sn(1) bond lengths are 3.30 Å. Sn(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form SnMg10Cd2 cuboctahedra that share corners with four equivalent Cd(1)Mg10Sn2 cuboctahedra, corners with six equivalent Sn(1)Mg10Cd2 cuboctahedra, corners with eight equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, edges with two equivalent Cd(1)Mg10Sn2 cuboctahedra, edges with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, faces with two equivalent Cd(1)Mg10Sn2 cuboctahedra, faces with two equivalent Sn(1)Mg10Cd2 cuboctahedra, faces with four equivalent Mg(1)Mg8Cd2Sn2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cd2 cuboctahedra.