Mg6MoFe crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), two equivalent Mo(1), and two equivalent Fe(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 Fe(1) atoms to form distorted MgMg10Fe2 cuboctahedra that share corners with four equivalent Fe(1)Mg10Mo2 cuboctahedra, corners with six equivalent Mg(2)Mg10Fe2 cuboctahedra, edges with two equivalent Fe(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mg(2)Mg10Fe2 cuboctahedra, faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra, and faces with six equivalent Mo(1)Mg10Fe2 cuboctahedra. In the third Mg site, Mg(3) 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 Mo(1), and two equivalent Fe(1) atoms. In the fourth Mg site, Mg(4) is bonded in a distorted linear geometry to two equivalent Mg(2), four equivalent Mg(3), and two equivalent Mo(1) atoms. Mo(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Fe(1) atoms to form MoMg10Fe2 cuboctahedra that share corners with six equivalent Mo(1)Mg10Fe2 cuboctahedra, edges with four equivalent Fe(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mo(1)Mg10Fe2 cuboctahedra, faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Fe2 cuboctahedra. Fe(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Mo(1) atoms to form distorted FeMg10Mo2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Fe2 cuboctahedra, corners with six equivalent Fe(1)Mg10Mo2 cuboctahedra, edges with two equivalent Mg(2)Mg10Fe2 cuboctahedra, edges with four equivalent Mo(1)Mg10Fe2 cuboctahedra, faces with two equivalent Mg(2)Mg10Fe2 cuboctahedra, faces with two equivalent Mo(1)Mg10Fe2 cuboctahedra, and faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra.
Mg6MoFe crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), two equivalent Mo(1), and two equivalent Fe(1) atoms. Both Mg(1)-Mg(2) bond lengths are 3.08 Å. Both Mg(1)-Mg(3) bond lengths are 2.94 Å. Both Mg(1)-Mo(1) bond lengths are 2.97 Å. There is one shorter (2.78 Å) and one longer (3.37 Å) Mg(1)-Fe(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 Fe(1) atoms to form distorted MgMg10Fe2 cuboctahedra that share corners with four equivalent Fe(1)Mg10Mo2 cuboctahedra, corners with six equivalent Mg(2)Mg10Fe2 cuboctahedra, edges with two equivalent Fe(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mg(2)Mg10Fe2 cuboctahedra, faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra, and faces with six equivalent Mo(1)Mg10Fe2 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 2.92 Å. All Mg(2)-Mg(3) bond lengths are 2.98 Å. Both Mg(2)-Fe(1) bond lengths are 2.97 Å. In the third Mg site, Mg(3) 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 Mo(1), and two equivalent Fe(1) atoms. There is one shorter (2.86 Å) and one longer (3.06 Å) Mg(3)-Mg(3) bond length. There is one shorter (3.04 Å) and one longer (3.12 Å) Mg(3)-Mg(4) bond length. There is one shorter (2.90 Å) and one longer (3.26 Å) Mg(3)-Mo(1) bond length. Both Mg(3)-Fe(1) bond lengths are 3.03 Å. In the fourth Mg site, Mg(4) is bonded in a distorted linear geometry to two equivalent Mg(2), four equivalent Mg(3), and two equivalent Mo(1) atoms. Both Mg(4)-Mo(1) bond lengths are 2.97 Å. Mo(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Fe(1) atoms to form MoMg10Fe2 cuboctahedra that share corners with six equivalent Mo(1)Mg10Fe2 cuboctahedra, edges with four equivalent Fe(1)Mg10Mo2 cuboctahedra, faces with two equivalent Mo(1)Mg10Fe2 cuboctahedra, faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Fe2 cuboctahedra. Both Mo(1)-Fe(1) bond lengths are 2.68 Å. Fe(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Mo(1) atoms to form distorted FeMg10Mo2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Fe2 cuboctahedra, corners with six equivalent Fe(1)Mg10Mo2 cuboctahedra, edges with two equivalent Mg(2)Mg10Fe2 cuboctahedra, edges with four equivalent Mo(1)Mg10Fe2 cuboctahedra, faces with two equivalent Mg(2)Mg10Fe2 cuboctahedra, faces with two equivalent Mo(1)Mg10Fe2 cuboctahedra, and faces with two equivalent Fe(1)Mg10Mo2 cuboctahedra.