Nd4Fe29Si5 crystallizes in the triclinic P-1 space group. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 19-coordinate geometry to one Fe(11), one Fe(13), one Fe(15), one Fe(16), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(8), one Fe(9), two equivalent Fe(10), two equivalent Fe(12), two equivalent Fe(2), two equivalent Fe(7), and one Si(2) atom. In the second Nd site, Nd(2) is bonded in a 19-coordinate geometry to one Fe(10), one Fe(12), one Fe(13), one Fe(14), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(8), two equivalent Fe(9), one Si(1), and one Si(3) atom. There are sixteen inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to two equivalent Nd(2), one Fe(11), one Fe(14), one Fe(3), one Fe(6), one Fe(9), two equivalent Fe(8), one Si(1), and two equivalent Si(3) atoms. In the second Fe site, Fe(2) is bonded to two equivalent Nd(1), one Fe(10), one Fe(12), one Fe(15), one Fe(16), one Fe(4), one Fe(5), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(7)Nd3Fe8Si cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Nd(1), one Nd(2), one Fe(1), one Fe(10), one Fe(11), one Fe(13), one Fe(6), one Fe(8), one Fe(9), one Si(1), and two equivalent Si(3) atoms. In the fourth Fe site, Fe(4) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(12), one Fe(13), one Fe(16), one Fe(2), one Fe(5), one Fe(7), one Fe(9), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(10)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Nd3Fe8Si cuboctahedra. In the fifth Fe site, Fe(5) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(15), one Fe(2), one Fe(4), one Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(12)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Nd3Fe8Si cuboctahedra. In the sixth Fe site, Fe(6) is bonded to one Nd(1), one Nd(2), one Fe(1), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(3), one Fe(8), one Fe(9), and two equivalent Si(3) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, faces with three equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(11)Nd3Fe8Si cuboctahedra. In the seventh Fe site, Fe(7) is bonded to one Nd(2), two equivalent Nd(1), one Fe(10), one Fe(12), one Fe(15), one Fe(16), one Fe(4), one Fe(5), two equivalent Fe(2), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Nd2Fe8Si2 cuboctahedra. In the eighth Fe site, Fe(8) is bonded to one Nd(1), two equivalent Nd(2), one Fe(11), one Fe(14), one Fe(3), one Fe(6), one Fe(9), two equivalent Fe(1), one Si(1), and one Si(3) atom to form distorted FeNd3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra. In the ninth Fe site, Fe(9) is bonded to one Nd(1), two equivalent Nd(2), one Fe(1), one Fe(12), one Fe(13), one Fe(3), one Fe(4), one Fe(6), one Fe(8), one Si(1), and one Si(3) atom to form distorted FeNd3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Nd(2), two equivalent Nd(1), one Fe(11), one Fe(13), one Fe(16), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(7), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(14)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. In the eleventh Fe site, Fe(11) is bonded to one Nd(1), two equivalent Nd(2), one Fe(1), one Fe(10), one Fe(13), one Fe(14), one Fe(3), one Fe(5), one Fe(6), one Fe(8), and one Si(3) atom to form distorted FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra. In the twelfth Fe site, Fe(12) is bonded to one Nd(2), two equivalent Nd(1), one Fe(13), one Fe(15), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(9), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra. In the thirteenth Fe site, Fe(13) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(11), one Fe(12), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(9), one Si(2), and one Si(3) atom to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with three equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with three equivalent Fe(7)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, and faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Nd(2), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(6), two equivalent Fe(8), and two equivalent Si(3) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(10)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Nd(1), two equivalent Fe(12), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Nd(1), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(11)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with four equivalent Fe(5)Nd2Fe8Si2 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to two equivalent Nd(2), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(8), two equivalent Fe(9), and two equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(10), one Fe(12), one Fe(13), one Fe(15), one Fe(16), one Fe(7), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), and one Si(2) atom. In the third Si site, Si(3) is bonded in a 14-coordinate geometry to one Nd(2), one Fe(11), one Fe(13), one Fe(14), one Fe(8), one Fe(9), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(6), one Si(1), and one Si(3) atom.
Nd4Fe29Si5 crystallizes in the triclinic P-1 space group. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 19-coordinate geometry to one Fe(11), one Fe(13), one Fe(15), one Fe(16), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(8), one Fe(9), two equivalent Fe(10), two equivalent Fe(12), two equivalent Fe(2), two equivalent Fe(7), and one Si(2) atom. The Nd(1)-Fe(11) bond length is 3.07 Å. The Nd(1)-Fe(13) bond length is 3.32 Å. The Nd(1)-Fe(15) bond length is 3.32 Å. The Nd(1)-Fe(16) bond length is 3.33 Å. The Nd(1)-Fe(3) bond length is 3.01 Å. The Nd(1)-Fe(4) bond length is 3.04 Å. The Nd(1)-Fe(5) bond length is 3.05 Å. The Nd(1)-Fe(6) bond length is 3.06 Å. The Nd(1)-Fe(8) bond length is 3.20 Å. The Nd(1)-Fe(9) bond length is 3.10 Å. There is one shorter (3.20 Å) and one longer (3.22 Å) Nd(1)-Fe(10) bond length. There is one shorter (3.21 Å) and one longer (3.25 Å) Nd(1)-Fe(12) bond length. There is one shorter (3.02 Å) and one longer (3.05 Å) Nd(1)-Fe(2) bond length. There is one shorter (3.08 Å) and one longer (3.23 Å) Nd(1)-Fe(7) bond length. The Nd(1)-Si(2) bond length is 3.08 Å. In the second Nd site, Nd(2) is bonded in a 19-coordinate geometry to one Fe(10), one Fe(12), one Fe(13), one Fe(14), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(8), two equivalent Fe(9), one Si(1), and one Si(3) atom. The Nd(2)-Fe(10) bond length is 3.09 Å. The Nd(2)-Fe(12) bond length is 3.07 Å. The Nd(2)-Fe(13) bond length is 3.31 Å. The Nd(2)-Fe(14) bond length is 3.30 Å. The Nd(2)-Fe(3) bond length is 3.04 Å. The Nd(2)-Fe(4) bond length is 3.02 Å. The Nd(2)-Fe(5) bond length is 3.04 Å. The Nd(2)-Fe(6) bond length is 3.05 Å. The Nd(2)-Fe(7) bond length is 3.18 Å. There is one shorter (3.00 Å) and one longer (3.03 Å) Nd(2)-Fe(1) bond length. There is one shorter (3.19 Å) and one longer (3.27 Å) Nd(2)-Fe(11) bond length. There is one shorter (3.12 Å) and one longer (3.20 Å) Nd(2)-Fe(8) bond length. There is one shorter (3.20 Å) and one longer (3.22 Å) Nd(2)-Fe(9) bond length. The Nd(2)-Si(1) bond length is 3.34 Å. The Nd(2)-Si(3) bond length is 3.10 Å. There are sixteen inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to two equivalent Nd(2), one Fe(11), one Fe(14), one Fe(3), one Fe(6), one Fe(9), two equivalent Fe(8), one Si(1), and two equivalent Si(3) atoms. The Fe(1)-Fe(11) bond length is 2.53 Å. The Fe(1)-Fe(14) bond length is 2.47 Å. The Fe(1)-Fe(3) bond length is 2.41 Å. The Fe(1)-Fe(6) bond length is 2.44 Å. The Fe(1)-Fe(9) bond length is 2.49 Å. There is one shorter (2.68 Å) and one longer (2.70 Å) Fe(1)-Fe(8) bond length. The Fe(1)-Si(1) bond length is 2.42 Å. There is one shorter (2.66 Å) and one longer (2.85 Å) Fe(1)-Si(3) bond length. In the second Fe site, Fe(2) is bonded to two equivalent Nd(1), one Fe(10), one Fe(12), one Fe(15), one Fe(16), one Fe(4), one Fe(5), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(7)Nd3Fe8Si cuboctahedra. The Fe(2)-Fe(10) bond length is 2.52 Å. The Fe(2)-Fe(12) bond length is 2.52 Å. The Fe(2)-Fe(15) bond length is 2.44 Å. The Fe(2)-Fe(16) bond length is 2.44 Å. The Fe(2)-Fe(4) bond length is 2.41 Å. The Fe(2)-Fe(5) bond length is 2.42 Å. There is one shorter (2.69 Å) and one longer (2.70 Å) Fe(2)-Fe(7) bond length. Both Fe(2)-Si(2) bond lengths are 2.74 Å. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Nd(1), one Nd(2), one Fe(1), one Fe(10), one Fe(11), one Fe(13), one Fe(6), one Fe(8), one Fe(9), one Si(1), and two equivalent Si(3) atoms. The Fe(3)-Fe(10) bond length is 2.69 Å. The Fe(3)-Fe(11) bond length is 2.52 Å. The Fe(3)-Fe(13) bond length is 2.47 Å. The Fe(3)-Fe(6) bond length is 2.44 Å. The Fe(3)-Fe(8) bond length is 2.50 Å. The Fe(3)-Fe(9) bond length is 2.68 Å. The Fe(3)-Si(1) bond length is 2.42 Å. There is one shorter (2.66 Å) and one longer (2.85 Å) Fe(3)-Si(3) bond length. In the fourth Fe site, Fe(4) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(12), one Fe(13), one Fe(16), one Fe(2), one Fe(5), one Fe(7), one Fe(9), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(10)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Nd3Fe8Si cuboctahedra. The Fe(4)-Fe(10) bond length is 2.70 Å. The Fe(4)-Fe(12) bond length is 2.52 Å. The Fe(4)-Fe(13) bond length is 2.44 Å. The Fe(4)-Fe(16) bond length is 2.44 Å. The Fe(4)-Fe(5) bond length is 2.43 Å. The Fe(4)-Fe(7) bond length is 2.52 Å. The Fe(4)-Fe(9) bond length is 2.69 Å. There is one shorter (2.74 Å) and one longer (2.75 Å) Fe(4)-Si(2) bond length. In the fifth Fe site, Fe(5) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(15), one Fe(2), one Fe(4), one Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(12)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Nd3Fe8Si cuboctahedra. The Fe(5)-Fe(10) bond length is 2.52 Å. The Fe(5)-Fe(11) bond length is 2.69 Å. The Fe(5)-Fe(12) bond length is 2.68 Å. The Fe(5)-Fe(13) bond length is 2.44 Å. The Fe(5)-Fe(15) bond length is 2.44 Å. The Fe(5)-Fe(7) bond length is 2.52 Å. Both Fe(5)-Si(2) bond lengths are 2.72 Å. In the sixth Fe site, Fe(6) is bonded to one Nd(1), one Nd(2), one Fe(1), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(3), one Fe(8), one Fe(9), and two equivalent Si(3) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, faces with three equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(11)Nd3Fe8Si cuboctahedra. The Fe(6)-Fe(11) bond length is 2.71 Å. The Fe(6)-Fe(12) bond length is 2.69 Å. The Fe(6)-Fe(13) bond length is 2.44 Å. The Fe(6)-Fe(14) bond length is 2.44 Å. The Fe(6)-Fe(8) bond length is 2.50 Å. The Fe(6)-Fe(9) bond length is 2.51 Å. There is one shorter (2.68 Å) and one longer (2.69 Å) Fe(6)-Si(3) bond length. In the seventh Fe site, Fe(7) is bonded to one Nd(2), two equivalent Nd(1), one Fe(10), one Fe(12), one Fe(15), one Fe(16), one Fe(4), one Fe(5), two equivalent Fe(2), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Nd2Fe8Si2 cuboctahedra. The Fe(7)-Fe(10) bond length is 2.50 Å. The Fe(7)-Fe(12) bond length is 2.47 Å. The Fe(7)-Fe(15) bond length is 2.44 Å. The Fe(7)-Fe(16) bond length is 2.42 Å. The Fe(7)-Si(2) bond length is 2.57 Å. In the eighth Fe site, Fe(8) is bonded to one Nd(1), two equivalent Nd(2), one Fe(11), one Fe(14), one Fe(3), one Fe(6), one Fe(9), two equivalent Fe(1), one Si(1), and one Si(3) atom to form distorted FeNd3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra. The Fe(8)-Fe(11) bond length is 2.46 Å. The Fe(8)-Fe(14) bond length is 2.41 Å. The Fe(8)-Fe(9) bond length is 2.54 Å. The Fe(8)-Si(1) bond length is 2.41 Å. The Fe(8)-Si(3) bond length is 2.60 Å. In the ninth Fe site, Fe(9) is bonded to one Nd(1), two equivalent Nd(2), one Fe(1), one Fe(12), one Fe(13), one Fe(3), one Fe(4), one Fe(6), one Fe(8), one Si(1), and one Si(3) atom to form distorted FeNd3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra. The Fe(9)-Fe(12) bond length is 2.48 Å. The Fe(9)-Fe(13) bond length is 2.42 Å. The Fe(9)-Si(1) bond length is 2.40 Å. The Fe(9)-Si(3) bond length is 2.61 Å. In the tenth Fe site, Fe(10) is bonded to one Nd(2), two equivalent Nd(1), one Fe(11), one Fe(13), one Fe(16), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(7), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(14)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. The Fe(10)-Fe(11) bond length is 2.45 Å. The Fe(10)-Fe(13) bond length is 2.44 Å. The Fe(10)-Fe(16) bond length is 2.42 Å. The Fe(10)-Si(2) bond length is 2.56 Å. In the eleventh Fe site, Fe(11) is bonded to one Nd(1), two equivalent Nd(2), one Fe(1), one Fe(10), one Fe(13), one Fe(14), one Fe(3), one Fe(5), one Fe(6), one Fe(8), and one Si(3) atom to form distorted FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(2)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(6)Nd2Fe8Si2 cuboctahedra. The Fe(11)-Fe(13) bond length is 2.43 Å. The Fe(11)-Fe(14) bond length is 2.43 Å. The Fe(11)-Si(3) bond length is 2.50 Å. In the twelfth Fe site, Fe(12) is bonded to one Nd(2), two equivalent Nd(1), one Fe(13), one Fe(15), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(9), and one Si(2) atom to form FeNd3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with three equivalent Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(13)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Nd2Fe8Si2 cuboctahedra. The Fe(12)-Fe(13) bond length is 2.42 Å. The Fe(12)-Fe(15) bond length is 2.42 Å. The Fe(12)-Si(2) bond length is 2.59 Å. In the thirteenth Fe site, Fe(13) is bonded to one Nd(1), one Nd(2), one Fe(10), one Fe(11), one Fe(12), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(9), one Si(2), and one Si(3) atom to form distorted FeNd2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Nd3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with three equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with three equivalent Fe(7)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(4)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Nd2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Nd3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Nd3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(14)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Nd2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Nd3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(11)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(12)Nd3Fe8Si cuboctahedra,  a faceface with one Fe(7)Nd3Fe8Si cuboctahedra, and faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra. The Fe(13)-Si(2) bond length is 2.57 Å. The Fe(13)-Si(3) bond length is 2.51 Å. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Nd(2), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(6), two equivalent Fe(8), and two equivalent Si(3) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(10)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Nd3Fe8Si cuboctahedra. Both Fe(14)-Si(3) bond lengths are 2.51 Å. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Nd(1), two equivalent Fe(12), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(16)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. Both Fe(15)-Si(2) bond lengths are 2.57 Å. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Nd(1), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(7), and two equivalent Si(2) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Nd2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Nd3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, corners with four equivalent Fe(11)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Fe(9)Nd3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(15)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Nd3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Nd3Fe8Si cuboctahedra, and faces with four equivalent Fe(5)Nd2Fe8Si2 cuboctahedra. Both Fe(16)-Si(2) bond lengths are 2.59 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to two equivalent Nd(2), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(8), two equivalent Fe(9), and two equivalent Si(3) atoms. Both Si(1)-Si(3) bond lengths are 2.73 Å. In the second Si site, Si(2) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(10), one Fe(12), one Fe(13), one Fe(15), one Fe(16), one Fe(7), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), and one Si(2) atom. The Si(2)-Si(2) bond length is 2.54 Å. In the third Si site, Si(3) is bonded in a 14-coordinate geometry to one Nd(2), one Fe(11), one Fe(13), one Fe(14), one Fe(8), one Fe(9), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(6), one Si(1), and one Si(3) atom. The Si(3)-Si(3) bond length is 2.51 Å.