The compound described by Y4Fe29Si5 crystallizes in the triclinic P-1 space group. There are two inequivalent Y sites. In the first Y site, Y(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 Y site, Y(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 11-coordinate geometry to two equivalent Y(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 in a 12-coordinate geometry to two equivalent Y(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. In the third Fe site, Fe(3) is bonded in a 11-coordinate geometry to one Y(1), one Y(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 in a 12-coordinate geometry to one Y(1), one Y(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. In the fifth Fe site, Fe(5) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with three equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Y3Fe8Si cuboctahedra. In the sixth Fe site, Fe(6) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, faces with three equivalent Fe(8)Y3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(11)Y3Fe8Si cuboctahedra. In the seventh Fe site, Fe(7) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Y2Fe8Si2 cuboctahedra. In the eighth Fe site, Fe(8) is bonded to one Y(1), two equivalent Y(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 FeY3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(6)Y2Fe8Si2 cuboctahedra. In the ninth Fe site, Fe(9) is bonded to one Y(1), two equivalent Y(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 FeY3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(14)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra. In the eleventh Fe site, Fe(11) is bonded to one Y(1), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(6)Y2Fe8Si2 cuboctahedra. In the twelfth Fe site, Fe(12) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Y2Fe8Si2 cuboctahedra. In the thirteenth Fe site, Fe(13) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with three equivalent Fe(7)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, and  a faceface with one Fe(7)Y3Fe8Si cuboctahedra. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(10)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, edges with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, edges with two equivalent Fe(10)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(11)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra, and faces with four equivalent Fe(5)Y2Fe8Si2 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to two equivalent Y(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 Y(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 Y(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. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y4Fe29Si5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.389
_cell_length_b   6.380
_cell_length_c   12.766
_cell_angle_alpha   81.520
_cell_angle_beta   82.452
_cell_angle_gamma   82.430
_symmetry_Int_Tables_number   1
_cell_volume   506.892
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Y  Y0  1  0.654  0.655  0.326  1.0
  Y  Y1  1  0.659  0.650  0.827  1.0
  Y  Y2  1  0.341  0.350  0.173  1.0
  Y  Y3  1  0.346  0.345  0.674  1.0
  Fe  Fe4  1  0.310  0.694  0.999  1.0
  Fe  Fe5  1  0.300  0.700  0.500  1.0
  Fe  Fe6  1  0.691  0.003  0.152  1.0
  Fe  Fe7  1  0.700  1.000  0.651  1.0
  Fe  Fe8  1  0.999  0.297  0.351  1.0
  Fe  Fe9  1  0.001  0.290  0.855  1.0
  Fe  Fe10  1  0.300  0.000  0.349  1.0
  Fe  Fe11  1  0.309  0.997  0.848  1.0
  Fe  Fe12  1  0.999  0.710  0.145  1.0
  Fe  Fe13  1  0.001  0.703  0.649  1.0
  Fe  Fe14  1  0.700  0.300  0.500  1.0
  Fe  Fe15  1  0.690  0.306  0.001  1.0
  Fe  Fe16  1  0.339  0.339  0.422  1.0
  Fe  Fe17  1  0.336  0.335  0.925  1.0
  Fe  Fe18  1  0.336  0.850  0.168  1.0
  Fe  Fe19  1  0.340  0.845  0.670  1.0
  Fe  Fe20  1  0.836  0.344  0.171  1.0
  Fe  Fe21  1  0.845  0.339  0.671  1.0
  Fe  Fe22  1  0.664  0.665  0.075  1.0
  Fe  Fe23  1  0.661  0.661  0.578  1.0
  Fe  Fe24  1  0.660  0.155  0.330  1.0
  Fe  Fe25  1  0.664  0.150  0.832  1.0
  Fe  Fe26  1  0.155  0.661  0.329  1.0
  Fe  Fe27  1  0.164  0.656  0.829  1.0
  Fe  Fe28  1  0.998  0.001  0.250  1.0
  Fe  Fe29  1  0.002  0.999  0.750  1.0
  Fe  Fe30  1  0.000  0.500  0.000  1.0
  Fe  Fe31  1  0.000  0.500  0.500  1.0
  Fe  Fe32  1  0.500  0.000  0.500  1.0
  Si  Si33  1  0.500  0.000  0.000  1.0
  Si  Si34  1  0.899  0.899  0.449  1.0
  Si  Si35  1  0.924  0.889  0.945  1.0
  Si  Si36  1  0.076  0.111  0.055  1.0
  Si  Si37  1  0.101  0.101  0.551  1.0
[/CIF]
.
The compound described by Y4Fe29Si5 crystallizes in the triclinic P-1 space group. There are two inequivalent Y sites. In the first Y site, Y(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 Y site, Y(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 11-coordinate geometry to two equivalent Y(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 in a 12-coordinate geometry to two equivalent Y(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. In the third Fe site, Fe(3) is bonded in a 11-coordinate geometry to one Y(1), one Y(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 in a 12-coordinate geometry to one Y(1), one Y(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. In the fifth Fe site, Fe(5) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with three equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(7)Y3Fe8Si cuboctahedra. In the sixth Fe site, Fe(6) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, faces with three equivalent Fe(8)Y3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(11)Y3Fe8Si cuboctahedra. In the seventh Fe site, Fe(7) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Y2Fe8Si2 cuboctahedra. In the eighth Fe site, Fe(8) is bonded to one Y(1), two equivalent Y(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 FeY3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(6)Y2Fe8Si2 cuboctahedra. In the ninth Fe site, Fe(9) is bonded to one Y(1), two equivalent Y(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 FeY3Fe7Si2 cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(14)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra. In the eleventh Fe site, Fe(11) is bonded to one Y(1), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(7)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(15)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra,  a faceface with one Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, and faces with three equivalent Fe(6)Y2Fe8Si2 cuboctahedra. In the twelfth Fe site, Fe(12) is bonded to one Y(2), two equivalent Y(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 FeY3Fe8Si cuboctahedra that share  a cornercorner with one Fe(13)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(8)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(13)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(14)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(16)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(13)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra, and faces with three equivalent Fe(5)Y2Fe8Si2 cuboctahedra. In the thirteenth Fe site, Fe(13) is bonded to one Y(1), one Y(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 FeY2Fe8Si2 cuboctahedra that share  a cornercorner with one Fe(14)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(15)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(16)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(5)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(6)Y2Fe8Si2 cuboctahedra,  a cornercorner with one Fe(9)Y3Fe7Si2 cuboctahedra,  a cornercorner with one Fe(10)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(11)Y3Fe8Si cuboctahedra,  a cornercorner with one Fe(12)Y3Fe8Si cuboctahedra, corners with three equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with three equivalent Fe(7)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(5)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(6)Y2Fe8Si2 cuboctahedra,  an edgeedge with one Fe(8)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(9)Y3Fe7Si2 cuboctahedra,  an edgeedge with one Fe(10)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(11)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(12)Y3Fe8Si cuboctahedra,  an edgeedge with one Fe(7)Y3Fe8Si cuboctahedra,  a faceface with one Fe(14)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(15)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(16)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(5)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(6)Y2Fe8Si2 cuboctahedra,  a faceface with one Fe(8)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(9)Y3Fe7Si2 cuboctahedra,  a faceface with one Fe(10)Y3Fe8Si cuboctahedra,  a faceface with one Fe(11)Y3Fe8Si cuboctahedra,  a faceface with one Fe(12)Y3Fe8Si cuboctahedra, and  a faceface with one Fe(7)Y3Fe8Si cuboctahedra. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(11)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(7)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(10)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, edges with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, faces with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, and faces with two equivalent Fe(11)Y3Fe8Si cuboctahedra. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, edges with two equivalent Fe(10)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(11)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(16)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, and faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Y(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 FeY2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(5)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(6)Y2Fe8Si2 cuboctahedra, corners with two equivalent Fe(8)Y3Fe7Si2 cuboctahedra, corners with two equivalent Fe(10)Y3Fe8Si cuboctahedra, corners with two equivalent Fe(12)Y3Fe8Si cuboctahedra, corners with four equivalent Fe(11)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(9)Y3Fe7Si2 cuboctahedra, edges with two equivalent Fe(12)Y3Fe8Si cuboctahedra, edges with two equivalent Fe(7)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(13)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(15)Y2Fe8Si2 cuboctahedra, faces with two equivalent Fe(10)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(12)Y3Fe8Si cuboctahedra, faces with two equivalent Fe(7)Y3Fe8Si cuboctahedra, and faces with four equivalent Fe(5)Y2Fe8Si2 cuboctahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to two equivalent Y(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 Y(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 Y(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. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y4Fe29Si5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.389
_cell_length_b   6.380
_cell_length_c   12.766
_cell_angle_alpha   81.520
_cell_angle_beta   82.452
_cell_angle_gamma   82.430
_symmetry_Int_Tables_number   1
_cell_volume   506.892
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Y  Y0  1  0.654  0.655  0.326  1.0
  Y  Y1  1  0.659  0.650  0.827  1.0
  Y  Y2  1  0.341  0.350  0.173  1.0
  Y  Y3  1  0.346  0.345  0.674  1.0
  Fe  Fe4  1  0.310  0.694  0.999  1.0
  Fe  Fe5  1  0.300  0.700  0.500  1.0
  Fe  Fe6  1  0.691  0.003  0.152  1.0
  Fe  Fe7  1  0.700  1.000  0.651  1.0
  Fe  Fe8  1  0.999  0.297  0.351  1.0
  Fe  Fe9  1  0.001  0.290  0.855  1.0
  Fe  Fe10  1  0.300  0.000  0.349  1.0
  Fe  Fe11  1  0.309  0.997  0.848  1.0
  Fe  Fe12  1  0.999  0.710  0.145  1.0
  Fe  Fe13  1  0.001  0.703  0.649  1.0
  Fe  Fe14  1  0.700  0.300  0.500  1.0
  Fe  Fe15  1  0.690  0.306  0.001  1.0
  Fe  Fe16  1  0.339  0.339  0.422  1.0
  Fe  Fe17  1  0.336  0.335  0.925  1.0
  Fe  Fe18  1  0.336  0.850  0.168  1.0
  Fe  Fe19  1  0.340  0.845  0.670  1.0
  Fe  Fe20  1  0.836  0.344  0.171  1.0
  Fe  Fe21  1  0.845  0.339  0.671  1.0
  Fe  Fe22  1  0.664  0.665  0.075  1.0
  Fe  Fe23  1  0.661  0.661  0.578  1.0
  Fe  Fe24  1  0.660  0.155  0.330  1.0
  Fe  Fe25  1  0.664  0.150  0.832  1.0
  Fe  Fe26  1  0.155  0.661  0.329  1.0
  Fe  Fe27  1  0.164  0.656  0.829  1.0
  Fe  Fe28  1  0.998  0.001  0.250  1.0
  Fe  Fe29  1  0.002  0.999  0.750  1.0
  Fe  Fe30  1  0.000  0.500  0.000  1.0
  Fe  Fe31  1  0.000  0.500  0.500  1.0
  Fe  Fe32  1  0.500  0.000  0.500  1.0
  Si  Si33  1  0.500  0.000  0.000  1.0
  Si  Si34  1  0.899  0.899  0.449  1.0
  Si  Si35  1  0.924  0.889  0.945  1.0
  Si  Si36  1  0.076  0.111  0.055  1.0
  Si  Si37  1  0.101  0.101  0.551  1.0
[/CIF]
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