Mo9Fe13 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the monoclinic C2/m space group. There are nine inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(2), one Mo(9), two equivalent Mo(3), two equivalent Mo(8), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. In the second Mo site, Mo(2) is bonded in a 7-coordinate geometry to one Mo(1), one Mo(2), four equivalent Mo(6), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. In the third Mo site, Mo(3) is bonded in a 7-coordinate geometry to one Mo(3), one Mo(4), two equivalent Mo(1), four equivalent Mo(8), two equivalent Fe(2), two equivalent Fe(5), and two equivalent Fe(9) atoms. In the fourth Mo site, Mo(4) is bonded in a 16-coordinate geometry to one Mo(3), one Mo(5), two equivalent Mo(7), one Fe(10), one Fe(8), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(9) atoms. In the fifth Mo site, Mo(5) is bonded in a 10-coordinate geometry to one Mo(4), one Mo(7), two equivalent Mo(6), two equivalent Fe(10), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(6) atoms. In the sixth Mo site, Mo(6) is bonded in a 15-coordinate geometry to one Mo(6), two equivalent Mo(5), four equivalent Mo(2), one Fe(10), one Fe(4), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. In the seventh Mo site, Mo(7) is bonded in a 16-coordinate geometry to one Mo(5), one Mo(9), two equivalent Mo(4), one Fe(4), one Fe(9), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(6), and two equivalent Fe(8) atoms. In the eighth Mo site, Mo(8) is bonded in a 15-coordinate geometry to one Mo(8), two equivalent Mo(1), four equivalent Mo(3), one Fe(1), one Fe(7), two equivalent Fe(2), two equivalent Fe(5), and two equivalent Fe(9) atoms. In the ninth Mo site, Mo(9) is bonded in a 16-coordinate geometry to one Mo(1), one Mo(7), two equivalent Mo(9), two equivalent Fe(3), three equivalent Fe(1), three equivalent Fe(8), and four equivalent Fe(2) atoms. There are ten inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Mo(8), two equivalent Mo(1), three equivalent Mo(9), one Fe(7), one Fe(8), two equivalent Fe(2), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(7)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, edges with four equivalent Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with three equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with six equivalent Fe(2)Fe5Mo7 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Mo(1), one Mo(3), one Mo(4), one Mo(7), one Mo(8), two equivalent Mo(9), one Fe(1), one Fe(8), one Fe(9), and two equivalent Fe(2) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with four equivalent Fe(2)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(2)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(1)Fe6Mo6 cuboctahedra, and faces with three equivalent Fe(8)Fe6Mo6 cuboctahedra. In the third Fe site, Fe(3) is bonded to one Mo(1), one Mo(2), one Mo(5), one Mo(6), one Mo(7), one Mo(9), one Fe(1), one Fe(10), one Fe(7), one Fe(8), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(6)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(5)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra,  a faceface with one Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(7)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(1)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra. In the fourth Fe site, Fe(4) is bonded to one Mo(6), one Mo(7), two equivalent Mo(4), two equivalent Mo(5), one Fe(10), one Fe(9), two equivalent Fe(5), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(3)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(4)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(8)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(10)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(6)Fe6Mo6 cuboctahedra. In the fifth Fe site, Fe(5) is bonded to one Mo(1), one Mo(2), one Mo(3), one Mo(4), one Mo(5), one Mo(6), one Mo(8), one Fe(4), one Fe(7), one Fe(9), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(6)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with three equivalent Fe(3)Fe6Mo6 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(2)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(7)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, and faces with two equivalent Fe(4)Fe6Mo6 cuboctahedra. In the sixth Fe site, Fe(6) is bonded to two equivalent Mo(4), two equivalent Mo(5), two equivalent Mo(7), two equivalent Fe(10), two equivalent Fe(4), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(10)Fe6Mo6 cuboctahedra, and faces with four equivalent Fe(4)Fe6Mo6 cuboctahedra. In the seventh Fe site, Fe(7) is bonded to one Mo(8), two equivalent Mo(1), two equivalent Mo(2), two equivalent Mo(6), one Fe(1), two equivalent Fe(3), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(1)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, edges with three equivalent Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra,  a faceface with one Fe(8)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra. In the eighth Fe site, Fe(8) is bonded to one Mo(4), two equivalent Mo(7), three equivalent Mo(9), one Fe(1), one Fe(10), two equivalent Fe(2), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(1)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(4)Fe6Mo6 cuboctahedra, edges with four equivalent Fe(8)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(1)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with six equivalent Fe(2)Fe5Mo7 cuboctahedra. In the ninth Fe site, Fe(9) is bonded to one Mo(7), two equivalent Mo(3), two equivalent Mo(4), two equivalent Mo(8), one Fe(4), two equivalent Fe(2), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(10)Fe6Mo6 cuboctahedra, edges with three equivalent Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(2)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Mo(4), one Mo(6), two equivalent Mo(5), two equivalent Mo(7), one Fe(4), one Fe(8), two equivalent Fe(3), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(9)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(8)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with three equivalent Fe(4)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with four equivalent Fe(6)Fe6Mo6 cuboctahedra.
Mo9Fe13 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the monoclinic C2/m space group. There are nine inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 16-coordinate geometry to one Mo(2), one Mo(9), two equivalent Mo(3), two equivalent Mo(8), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. The Mo(1)-Mo(2) bond length is 2.69 Å. The Mo(1)-Mo(9) bond length is 2.86 Å. There is one shorter (3.03 Å) and one longer (3.17 Å) Mo(1)-Mo(3) bond length. Both Mo(1)-Mo(8) bond lengths are 2.78 Å. Both Mo(1)-Fe(1) bond lengths are 2.77 Å. Both Mo(1)-Fe(2) bond lengths are 2.66 Å. Both Mo(1)-Fe(3) bond lengths are 2.81 Å. Both Mo(1)-Fe(5) bond lengths are 2.84 Å. Both Mo(1)-Fe(7) bond lengths are 2.81 Å. In the second Mo site, Mo(2) is bonded in a 7-coordinate geometry to one Mo(1), one Mo(2), four equivalent Mo(6), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. The Mo(2)-Mo(2) bond length is 2.47 Å. There are two shorter (2.98 Å) and two longer (2.99 Å) Mo(2)-Mo(6) bond lengths. Both Mo(2)-Fe(3) bond lengths are 2.58 Å. Both Mo(2)-Fe(5) bond lengths are 2.58 Å. Both Mo(2)-Fe(7) bond lengths are 2.61 Å. In the third Mo site, Mo(3) is bonded in a 7-coordinate geometry to one Mo(3), one Mo(4), two equivalent Mo(1), four equivalent Mo(8), two equivalent Fe(2), two equivalent Fe(5), and two equivalent Fe(9) atoms. The Mo(3)-Mo(3) bond length is 2.49 Å. The Mo(3)-Mo(4) bond length is 2.68 Å. There are two shorter (2.96 Å) and two longer (3.01 Å) Mo(3)-Mo(8) bond lengths. Both Mo(3)-Fe(2) bond lengths are 2.64 Å. Both Mo(3)-Fe(5) bond lengths are 2.62 Å. Both Mo(3)-Fe(9) bond lengths are 2.60 Å. In the fourth Mo site, Mo(4) is bonded in a 16-coordinate geometry to one Mo(3), one Mo(5), two equivalent Mo(7), one Fe(10), one Fe(8), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(9) atoms. The Mo(4)-Mo(5) bond length is 2.83 Å. Both Mo(4)-Mo(7) bond lengths are 2.85 Å. The Mo(4)-Fe(10) bond length is 2.65 Å. The Mo(4)-Fe(8) bond length is 2.80 Å. Both Mo(4)-Fe(2) bond lengths are 2.85 Å. Both Mo(4)-Fe(4) bond lengths are 2.72 Å. Both Mo(4)-Fe(5) bond lengths are 2.81 Å. Both Mo(4)-Fe(6) bond lengths are 2.68 Å. Both Mo(4)-Fe(9) bond lengths are 2.82 Å. In the fifth Mo site, Mo(5) is bonded in a 10-coordinate geometry to one Mo(4), one Mo(7), two equivalent Mo(6), two equivalent Fe(10), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(6) atoms. The Mo(5)-Mo(7) bond length is 2.91 Å. Both Mo(5)-Mo(6) bond lengths are 2.80 Å. Both Mo(5)-Fe(10) bond lengths are 2.78 Å. Both Mo(5)-Fe(3) bond lengths are 2.71 Å. Both Mo(5)-Fe(4) bond lengths are 2.77 Å. Both Mo(5)-Fe(5) bond lengths are 2.75 Å. Both Mo(5)-Fe(6) bond lengths are 2.74 Å. In the sixth Mo site, Mo(6) is bonded in a 15-coordinate geometry to one Mo(6), two equivalent Mo(5), four equivalent Mo(2), one Fe(10), one Fe(4), two equivalent Fe(3), two equivalent Fe(5), and two equivalent Fe(7) atoms. The Mo(6)-Mo(6) bond length is 2.74 Å. The Mo(6)-Fe(10) bond length is 2.65 Å. The Mo(6)-Fe(4) bond length is 2.65 Å. Both Mo(6)-Fe(3) bond lengths are 2.69 Å. Both Mo(6)-Fe(5) bond lengths are 2.74 Å. There is one shorter (2.73 Å) and one longer (2.75 Å) Mo(6)-Fe(7) bond length. In the seventh Mo site, Mo(7) is bonded in a 16-coordinate geometry to one Mo(5), one Mo(9), two equivalent Mo(4), one Fe(4), one Fe(9), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(6), and two equivalent Fe(8) atoms. The Mo(7)-Mo(9) bond length is 2.85 Å. The Mo(7)-Fe(4) bond length is 2.74 Å. The Mo(7)-Fe(9) bond length is 2.73 Å. Both Mo(7)-Fe(10) bond lengths are 2.75 Å. Both Mo(7)-Fe(2) bond lengths are 2.76 Å. Both Mo(7)-Fe(3) bond lengths are 2.75 Å. Both Mo(7)-Fe(6) bond lengths are 2.78 Å. Both Mo(7)-Fe(8) bond lengths are 2.78 Å. In the eighth Mo site, Mo(8) is bonded in a 15-coordinate geometry to one Mo(8), two equivalent Mo(1), four equivalent Mo(3), one Fe(1), one Fe(7), two equivalent Fe(2), two equivalent Fe(5), and two equivalent Fe(9) atoms. The Mo(8)-Mo(8) bond length is 2.72 Å. The Mo(8)-Fe(1) bond length is 2.75 Å. The Mo(8)-Fe(7) bond length is 2.59 Å. Both Mo(8)-Fe(2) bond lengths are 2.83 Å. Both Mo(8)-Fe(5) bond lengths are 2.67 Å. There is one shorter (2.70 Å) and one longer (2.77 Å) Mo(8)-Fe(9) bond length. In the ninth Mo site, Mo(9) is bonded in a 16-coordinate geometry to one Mo(1), one Mo(7), two equivalent Mo(9), two equivalent Fe(3), three equivalent Fe(1), three equivalent Fe(8), and four equivalent Fe(2) atoms. Both Mo(9)-Mo(9) bond lengths are 2.91 Å. Both Mo(9)-Fe(3) bond lengths are 2.72 Å. There is one shorter (2.71 Å) and two longer (2.73 Å) Mo(9)-Fe(1) bond lengths. All Mo(9)-Fe(8) bond lengths are 2.72 Å. There are two shorter (2.79 Å) and two longer (2.83 Å) Mo(9)-Fe(2) bond lengths. There are ten inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Mo(8), two equivalent Mo(1), three equivalent Mo(9), one Fe(7), one Fe(8), two equivalent Fe(2), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(7)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, edges with four equivalent Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with three equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with six equivalent Fe(2)Fe5Mo7 cuboctahedra. The Fe(1)-Fe(7) bond length is 2.41 Å. The Fe(1)-Fe(8) bond length is 2.33 Å. Both Fe(1)-Fe(2) bond lengths are 2.35 Å. Both Fe(1)-Fe(3) bond lengths are 2.41 Å. In the second Fe site, Fe(2) is bonded to one Mo(1), one Mo(3), one Mo(4), one Mo(7), one Mo(8), two equivalent Mo(9), one Fe(1), one Fe(8), one Fe(9), and two equivalent Fe(2) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with four equivalent Fe(2)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(2)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(1)Fe6Mo6 cuboctahedra, and faces with three equivalent Fe(8)Fe6Mo6 cuboctahedra. The Fe(2)-Fe(8) bond length is 2.32 Å. The Fe(2)-Fe(9) bond length is 2.34 Å. There is one shorter (2.34 Å) and one longer (2.36 Å) Fe(2)-Fe(2) bond length. In the third Fe site, Fe(3) is bonded to one Mo(1), one Mo(2), one Mo(5), one Mo(6), one Mo(7), one Mo(9), one Fe(1), one Fe(10), one Fe(7), one Fe(8), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(6)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(5)Fe5Mo7 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(5)Fe5Mo7 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra,  a faceface with one Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(7)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(1)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra. The Fe(3)-Fe(10) bond length is 2.34 Å. The Fe(3)-Fe(7) bond length is 2.38 Å. The Fe(3)-Fe(8) bond length is 2.44 Å. There is one shorter (2.24 Å) and one longer (2.45 Å) Fe(3)-Fe(3) bond length. In the fourth Fe site, Fe(4) is bonded to one Mo(6), one Mo(7), two equivalent Mo(4), two equivalent Mo(5), one Fe(10), one Fe(9), two equivalent Fe(5), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(3)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(4)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(8)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(10)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(6)Fe6Mo6 cuboctahedra. The Fe(4)-Fe(10) bond length is 2.45 Å. The Fe(4)-Fe(9) bond length is 2.36 Å. Both Fe(4)-Fe(5) bond lengths are 2.36 Å. Both Fe(4)-Fe(6) bond lengths are 2.38 Å. In the fifth Fe site, Fe(5) is bonded to one Mo(1), one Mo(2), one Mo(3), one Mo(4), one Mo(5), one Mo(6), one Mo(8), one Fe(4), one Fe(7), one Fe(9), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(6)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(8)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with three equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with three equivalent Fe(3)Fe6Mo6 cuboctahedra,  an edgeedge with one Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(2)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(3)Fe6Mo6 cuboctahedra,  a faceface with one Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(7)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, and faces with two equivalent Fe(4)Fe6Mo6 cuboctahedra. The Fe(5)-Fe(7) bond length is 2.38 Å. The Fe(5)-Fe(9) bond length is 2.43 Å. There is one shorter (2.29 Å) and one longer (2.41 Å) Fe(5)-Fe(5) bond length. In the sixth Fe site, Fe(6) is bonded to two equivalent Mo(4), two equivalent Mo(5), two equivalent Mo(7), two equivalent Fe(10), two equivalent Fe(4), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(2)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(3)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(10)Fe6Mo6 cuboctahedra, and faces with four equivalent Fe(4)Fe6Mo6 cuboctahedra. Both Fe(6)-Fe(10) bond lengths are 2.37 Å. Both Fe(6)-Fe(6) bond lengths are 2.35 Å. In the seventh Fe site, Fe(7) is bonded to one Mo(8), two equivalent Mo(1), two equivalent Mo(2), two equivalent Mo(6), one Fe(1), two equivalent Fe(3), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(1)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, edges with three equivalent Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra,  a faceface with one Fe(8)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra. In the eighth Fe site, Fe(8) is bonded to one Mo(4), two equivalent Mo(7), three equivalent Mo(9), one Fe(1), one Fe(10), two equivalent Fe(2), and two equivalent Fe(3) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(1)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(4)Fe6Mo6 cuboctahedra, edges with four equivalent Fe(8)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(10)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(9)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with three equivalent Fe(1)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with six equivalent Fe(2)Fe5Mo7 cuboctahedra. The Fe(8)-Fe(10) bond length is 2.39 Å. In the ninth Fe site, Fe(9) is bonded to one Mo(7), two equivalent Mo(3), two equivalent Mo(4), two equivalent Mo(8), one Fe(4), two equivalent Fe(2), and two equivalent Fe(5) atoms to form FeFe5Mo7 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(1)Fe6Mo6 cuboctahedra,  a cornercorner with one Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(5)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(3)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(6)Fe6Mo6 cuboctahedra, edges with two equivalent Fe(10)Fe6Mo6 cuboctahedra, edges with three equivalent Fe(9)Fe5Mo7 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(4)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(6)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(8)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(2)Fe5Mo7 cuboctahedra, and faces with four equivalent Fe(5)Fe5Mo7 cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Mo(4), one Mo(6), two equivalent Mo(5), two equivalent Mo(7), one Fe(4), one Fe(8), two equivalent Fe(3), and two equivalent Fe(6) atoms to form FeFe6Mo6 cuboctahedra that share  a cornercorner with one Fe(7)Fe5Mo7 cuboctahedra,  a cornercorner with one Fe(9)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(2)Fe5Mo7 cuboctahedra, corners with two equivalent Fe(10)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(4)Fe6Mo6 cuboctahedra, corners with two equivalent Fe(8)Fe6Mo6 cuboctahedra, corners with four equivalent Fe(5)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(9)Fe5Mo7 cuboctahedra, edges with two equivalent Fe(10)Fe6Mo6 cuboctahedra,  a faceface with one Fe(7)Fe5Mo7 cuboctahedra,  a faceface with one Fe(1)Fe6Mo6 cuboctahedra,  a faceface with one Fe(8)Fe6Mo6 cuboctahedra, faces with two equivalent Fe(2)Fe5Mo7 cuboctahedra, faces with two equivalent Fe(5)Fe5Mo7 cuboctahedra, faces with three equivalent Fe(4)Fe6Mo6 cuboctahedra, faces with four equivalent Fe(3)Fe6Mo6 cuboctahedra, and faces with four equivalent Fe(6)Fe6Mo6 cuboctahedra.