RbMg6Y is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form distorted RbY2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Rb2Mg10 cuboctahedra, corners with six equivalent Rb(1)Y2Mg10 cuboctahedra, edges with two equivalent Mg(4)Rb2Mg10 cuboctahedra, edges with four equivalent Y(1)Rb2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Mg(2)Y2Mg10 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Rb(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Y(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form MgY2Mg10 cuboctahedra that share corners with four equivalent Y(1)Rb2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y2Mg10 cuboctahedra, edges with two equivalent Y(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Rb(1)Y2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Rb(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Y(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Rb(1), two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgRb2Mg10 cuboctahedra that share corners with four equivalent Rb(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(4)Rb2Mg10 cuboctahedra, edges with two equivalent Rb(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, and faces with six equivalent Y(1)Rb2Mg10 cuboctahedra. Y(1) is bonded to two equivalent Rb(1), two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms to form YRb2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Y2Mg10 cuboctahedra, corners with six equivalent Y(1)Rb2Mg10 cuboctahedra, edges with two equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Rb2Mg10 cuboctahedra.
RbMg6Y is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form distorted RbY2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Rb2Mg10 cuboctahedra, corners with six equivalent Rb(1)Y2Mg10 cuboctahedra, edges with two equivalent Mg(4)Rb2Mg10 cuboctahedra, edges with four equivalent Y(1)Rb2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Mg(2)Y2Mg10 cuboctahedra. Both Rb(1)-Mg(4) bond lengths are 3.53 Å. All Rb(1)-Mg(1) bond lengths are 3.40 Å. There are two shorter (3.37 Å) and two longer (3.50 Å) Rb(1)-Mg(3) bond lengths. Both Rb(1)-Y(1) bond lengths are 3.62 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Rb(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Y(1) atoms. The Mg(1)-Mg(1) bond length is 3.31 Å. Both Mg(1)-Mg(2) bond lengths are 3.43 Å. Both Mg(1)-Mg(3) bond lengths are 3.43 Å. Both Mg(1)-Mg(4) bond lengths are 3.33 Å. There is one shorter (3.25 Å) and one longer (3.61 Å) Mg(1)-Y(1) bond length. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form MgY2Mg10 cuboctahedra that share corners with four equivalent Y(1)Rb2Mg10 cuboctahedra, corners with six equivalent Mg(2)Y2Mg10 cuboctahedra, edges with two equivalent Y(1)Rb2Mg10 cuboctahedra, edges with four equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Rb(1)Y2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.44 Å. All Mg(2)-Mg(3) bond lengths are 3.41 Å. Both Mg(2)-Y(1) bond lengths are 3.53 Å. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Rb(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Y(1) atoms. The Mg(3)-Mg(3) bond length is 3.32 Å. There is one shorter (3.43 Å) and one longer (3.44 Å) Mg(3)-Mg(4) bond length. Both Mg(3)-Y(1) bond lengths are 3.28 Å. In the fourth Mg site, Mg(4) is bonded to two equivalent Rb(1), two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgRb2Mg10 cuboctahedra that share corners with four equivalent Rb(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(4)Rb2Mg10 cuboctahedra, edges with two equivalent Rb(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Rb2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, and faces with six equivalent Y(1)Rb2Mg10 cuboctahedra. Y(1) is bonded to two equivalent Rb(1), two equivalent Mg(2), four equivalent Mg(1), and four equivalent Mg(3) atoms to form YRb2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Y2Mg10 cuboctahedra, corners with six equivalent Y(1)Rb2Mg10 cuboctahedra, edges with two equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Rb(1)Y2Mg10 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Y(1)Rb2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Rb2Mg10 cuboctahedra.