Mg6YCo crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Y(1), and two equivalent Co(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 distorted MgY2Mg10 cuboctahedra that share corners with six equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg10Co2 cuboctahedra, edges with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, and faces with six equivalent Co(1)Y2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Y(1), and two equivalent Co(1) atoms to form distorted MgY2Mg8Co2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Co2 cuboctahedra, corners with four equivalent Co(1)Y2Mg10 cuboctahedra, corners with ten equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Co2 cuboctahedra, edges with two equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, and faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Co(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Co2 cuboctahedra, corners with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, and faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra. Y(1) is bonded in a 2-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms. Co(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 CoY2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Co2 cuboctahedra, corners with six equivalent Co(1)Y2Mg10 cuboctahedra, corners with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Co2 cuboctahedra, edges with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, and faces with six equivalent Mg(2)Y2Mg10 cuboctahedra.
Mg6YCo crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Y(1), and two equivalent Co(1) atoms. There is one shorter (3.02 Å) and one longer (3.20 Å) Mg(1)-Mg(1) bond length. There is one shorter (3.08 Å) and one longer (3.39 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 2.94 Å. Both Mg(1)-Mg(4) bond lengths are 3.14 Å. There is one shorter (3.04 Å) and one longer (3.43 Å) Mg(1)-Y(1) bond length. Both Mg(1)-Co(1) bond lengths are 3.04 Å. 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 distorted MgY2Mg10 cuboctahedra that share corners with six equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg10Co2 cuboctahedra, edges with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, and faces with six equivalent Co(1)Y2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.05 Å. All Mg(2)-Mg(3) bond lengths are 3.07 Å. Both Mg(2)-Y(1) bond lengths are 3.13 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Y(1), and two equivalent Co(1) atoms to form distorted MgY2Mg8Co2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Co2 cuboctahedra, corners with four equivalent Co(1)Y2Mg10 cuboctahedra, corners with ten equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Co2 cuboctahedra, edges with two equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, and faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra. There is one shorter (3.06 Å) and one longer (3.16 Å) Mg(3)-Mg(3) bond length. There is one shorter (3.21 Å) and one longer (3.26 Å) Mg(3)-Mg(4) bond length. Both Mg(3)-Y(1) bond lengths are 3.23 Å. There is one shorter (3.06 Å) and one longer (3.41 Å) Mg(3)-Co(1) bond length. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Co(1)Y2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Co2 cuboctahedra, corners with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Y2Mg10 cuboctahedra, edges with four equivalent Mg(2)Y2Mg10 cuboctahedra, edges with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Y2Mg10 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, and faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra. Both Mg(4)-Co(1) bond lengths are 3.12 Å. Y(1) is bonded in a 2-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms. Both Y(1)-Co(1) bond lengths are 2.93 Å. Co(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 CoY2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Co2 cuboctahedra, corners with six equivalent Co(1)Y2Mg10 cuboctahedra, corners with eight equivalent Mg(3)Y2Mg8Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Co2 cuboctahedra, edges with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Co2 cuboctahedra, faces with two equivalent Co(1)Y2Mg10 cuboctahedra, faces with four equivalent Mg(3)Y2Mg8Co2 cuboctahedra, and faces with six equivalent Mg(2)Y2Mg10 cuboctahedra.