Mg6MoBi crystallizes in the orthorhombic Amm2 space group. There are five 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 Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with ten Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra. In the second 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 Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with ten Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra. In the third Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra, edges with two equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, edges with four equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra, edges with four equivalent Mo(1)Mg10Bi2 cuboctahedra, edges with four equivalent Bi(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra, faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra, faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra, faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra. In the fourth Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(2); and two equivalent Mo(1) atoms. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(3); four Mg(1,1); four equivalent Mg(2); and two equivalent Bi(1) atoms to form distorted MgMg10Bi2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; edges with four equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; and faces with six equivalent Mo(1)Mg10Bi2 cuboctahedra. Mo(1) is bonded to two equivalent Mg(3); four Mg(1,1); four equivalent Mg(2); and two equivalent Bi(1) atoms to form MoMg10Bi2 cuboctahedra that share corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with six equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Bi2 cuboctahedra. Bi(1) is bonded to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(2); and two equivalent Mo(1) atoms to form BiMg10Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with six equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra.
Mg6MoBi crystallizes in the orthorhombic Amm2 space group. There are five 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 Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with ten Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra. There is one shorter (3.08 Å) and one longer (3.12 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(2) bond lengths are 3.15 Å. Both Mg(1)-Mg(3) bond lengths are 3.15 Å. Both Mg(1)-Mg(4) bond lengths are 3.12 Å. Both Mg(1)-Mo(1) bond lengths are 3.14 Å. There is one shorter (3.13 Å) and one longer (3.15 Å) Mg(1)-Bi(1) bond length. In the second 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 Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with ten Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra. Both Mg(1)-Mg(2) bond lengths are 3.15 Å. Both Mg(1)-Mg(3) bond lengths are 3.15 Å. Both Mg(1)-Mg(4) bond lengths are 3.12 Å. Both Mg(1)-Mo(1) bond lengths are 3.14 Å. There is one shorter (3.13 Å) and one longer (3.15 Å) Mg(1)-Bi(1) bond length. In the third Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mo(1), and two equivalent Bi(1) atoms to form distorted MgMg8Bi2Mo2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Bi2 cuboctahedra, corners with ten equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, edges with two equivalent Mg(4)Mg10Bi2 cuboctahedra, edges with two equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, edges with four equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra, edges with four equivalent Mo(1)Mg10Bi2 cuboctahedra, edges with four equivalent Bi(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra, faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra, faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra, faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra, and faces with eight equivalent Mg(1)Mg8Bi2Mo2 cuboctahedra. There is one shorter (2.90 Å) and one longer (3.30 Å) Mg(2)-Mg(2) bond length. There is one shorter (3.03 Å) and one longer (3.26 Å) Mg(2)-Mg(3) bond length. There is one shorter (3.05 Å) and one longer (3.24 Å) Mg(2)-Mg(4) bond length. Both Mg(2)-Mo(1) bond lengths are 3.08 Å. Both Mg(2)-Bi(1) bond lengths are 3.19 Å. In the fourth Mg site, Mg(3) is bonded in a distorted water-like geometry to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(2); and two equivalent Mo(1) atoms. Both Mg(3)-Mg(4) bond lengths are 3.10 Å. Both Mg(3)-Mo(1) bond lengths are 3.11 Å. In the fifth Mg site, Mg(4) is bonded to two equivalent Mg(3); four Mg(1,1); four equivalent Mg(2); and two equivalent Bi(1) atoms to form distorted MgMg10Bi2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Bi2 cuboctahedra; corners with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; edges with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; edges with four equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; and faces with six equivalent Mo(1)Mg10Bi2 cuboctahedra. Both Mg(4)-Bi(1) bond lengths are 3.17 Å. Mo(1) is bonded to two equivalent Mg(3); four Mg(1,1); four equivalent Mg(2); and two equivalent Bi(1) atoms to form MoMg10Bi2 cuboctahedra that share corners with four equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with six equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Bi(1)Mg10Mo2 cuboctahedra; edges with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Bi2 cuboctahedra. Both Mo(1)-Bi(1) bond lengths are 3.10 Å. Bi(1) is bonded to two equivalent Mg(4); four Mg(1,1); four equivalent Mg(2); and two equivalent Mo(1) atoms to form BiMg10Mo2 cuboctahedra that share corners with four equivalent Mo(1)Mg10Bi2 cuboctahedra; corners with six equivalent Bi(1)Mg10Mo2 cuboctahedra; corners with eight Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with two equivalent Mo(1)Mg10Bi2 cuboctahedra; edges with four equivalent Mg(4)Mg10Bi2 cuboctahedra; edges with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; edges with eight equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra; faces with two equivalent Mg(4)Mg10Bi2 cuboctahedra; faces with two equivalent Mo(1)Mg10Bi2 cuboctahedra; faces with two equivalent Bi(1)Mg10Mo2 cuboctahedra; faces with four Mg(1,1)Mg8Bi2Mo2 cuboctahedra; and faces with four equivalent Mg(2)Mg8Bi2Mo2 cuboctahedra.