RbMg6Cd crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form RbMg10Cd2 cuboctahedra that share corners with four equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with six equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Cd(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cd2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Rb(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Cd(1) atoms to form distorted MgRb2Mg8Cd2 cuboctahedra that share corners with four equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with four equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Rb(1)Mg10Cd2 cuboctahedra, edges with two equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Cd(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Rb(1), one Mg(2), one Mg(3), two equivalent Mg(1), two equivalent Mg(4), and two equivalent Cd(1) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Rb(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(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)Rb2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, and faces with six equivalent Rb(1)Mg10Cd2 cuboctahedra. Cd(1) is bonded to two equivalent Rb(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form CdRb2Mg10 cuboctahedra that share corners with four equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with six equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Rb(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra.
RbMg6Cd crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cd(1) atoms to form RbMg10Cd2 cuboctahedra that share corners with four equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with six equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Cd(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cd2 cuboctahedra. Both Rb(1)-Mg(3) bond lengths are 3.45 Å. There are two shorter (3.43 Å) and two longer (3.44 Å) Rb(1)-Mg(1) bond lengths. All Rb(1)-Mg(2) bond lengths are 3.44 Å. Both Rb(1)-Cd(1) bond lengths are 3.40 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Rb(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Cd(1) atoms to form distorted MgRb2Mg8Cd2 cuboctahedra that share corners with four equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with four equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Rb(1)Mg10Cd2 cuboctahedra, edges with two equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Cd(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra. There is one shorter (3.33 Å) and one longer (3.48 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(2) bond lengths are 3.32 Å. Both Mg(1)-Mg(3) bond lengths are 3.30 Å. Both Mg(1)-Mg(4) bond lengths are 3.38 Å. There is one shorter (3.37 Å) and one longer (3.50 Å) Mg(1)-Cd(1) bond length. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Rb(1), one Mg(2), one Mg(3), two equivalent Mg(1), two equivalent Mg(4), and two equivalent Cd(1) atoms. The Mg(2)-Mg(2) bond length is 3.16 Å. The Mg(2)-Mg(3) bond length is 3.20 Å. There is one shorter (3.43 Å) and one longer (3.44 Å) Mg(2)-Mg(4) bond length. Both Mg(2)-Cd(1) bond lengths are 3.30 Å. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Rb(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(1) atoms. Both Mg(3)-Mg(4) bond lengths are 3.41 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)Rb2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, and faces with six equivalent Rb(1)Mg10Cd2 cuboctahedra. Both Mg(4)-Cd(1) bond lengths are 3.39 Å. Cd(1) is bonded to two equivalent Rb(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form CdRb2Mg10 cuboctahedra that share corners with four equivalent Rb(1)Mg10Cd2 cuboctahedra, corners with six equivalent Cd(1)Rb2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, edges with two equivalent Rb(1)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cd2 cuboctahedra, edges with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra, faces with two equivalent Rb(1)Mg10Cd2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cd2 cuboctahedra, faces with two equivalent Cd(1)Rb2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Rb2Mg8Cd2 cuboctahedra.