Sm2Fe15Co2 crystallizes in the monoclinic Cm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 19-coordinate geometry to one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), four equivalent Fe(9), and two equivalent Co(1) atoms. In the second Sm site, Sm(2) is bonded in a 19-coordinate geometry to one Fe(10), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(8), two equivalent Fe(9), and four equivalent Co(1) atoms. There are ten inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(1), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(8), two equivalent Fe(9), and one Co(1) atom. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(1), one Fe(10), one Fe(3), one Fe(6), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(4), and one Co(1) atom. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(10), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(9), and two equivalent Co(1) atoms. In the fourth Fe site, Fe(4) is bonded to one Sm(1), one Sm(2), one Fe(1), one Fe(10), one Fe(3), one Fe(6), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(2), and one Co(1) atom to form distorted FeSm2Fe9Co cuboctahedra that share  a cornercorner with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a cornercorner with one Fe(8)Sm3Fe9 cuboctahedra, corners with two equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with four equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with four equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra. In the fifth Fe site, Fe(5) is bonded to one Sm(1), one Sm(2), one Fe(6), one Fe(7), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(9), and two equivalent Co(1) atoms to form distorted FeSm2Fe8Co2 cuboctahedra that share corners with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with two equivalent Co(1)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with three equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, faces with two equivalent Co(1)Sm3Fe9 cuboctahedra, and faces with four equivalent Fe(4)Sm2Fe9Co cuboctahedra. In the sixth Fe site, Fe(6) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(10), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Fe(9) atoms. In the seventh Fe site, Fe(7) is bonded in a 14-coordinate geometry to one Sm(2), one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Co(1) atoms. In the eighth Fe site, Fe(8) is bonded to one Sm(1), two equivalent Sm(2), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and two equivalent Fe(9) atoms to form FeSm3Fe9 cuboctahedra that share corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with two equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with six equivalent Fe(9)Sm3Fe8Co cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with four equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with four equivalent Co(1)Sm3Fe9 cuboctahedra. In the ninth Fe site, Fe(9) is bonded to one Sm(2), two equivalent Sm(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), and one Co(1) atom to form FeSm3Fe8Co cuboctahedra that share  a cornercorner with one Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with three equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with five equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Co(1)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra. In the tenth Fe site, Fe(10) is bonded to one Sm(2), two equivalent Sm(1), one Fe(6), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Co(1) atoms to form FeSm3Fe7Co2 cuboctahedra that share corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with two equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with six equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with four equivalent Fe(9)Sm3Fe8Co cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Co(1)Sm3Fe9 cuboctahedra, and faces with four equivalent Fe(9)Sm3Fe8Co cuboctahedra. Co(1) is bonded to one Sm(1), two equivalent Sm(2), one Fe(1), one Fe(10), one Fe(2), one Fe(4), one Fe(5), one Fe(7), one Fe(9), and two equivalent Fe(3) atoms to form distorted CoSm3Fe9 cuboctahedra that share  a cornercorner with one Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Co(1)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with five equivalent Fe(9)Sm3Fe8Co cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with two equivalent Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, faces with two equivalent Fe(8)Sm3Fe9 cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra.
Sm2Fe15Co2 crystallizes in the monoclinic Cm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 19-coordinate geometry to one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), two equivalent Fe(10), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), four equivalent Fe(9), and two equivalent Co(1) atoms. The Sm(1)-Fe(5) bond length is 3.28 Å. The Sm(1)-Fe(6) bond length is 3.08 Å. The Sm(1)-Fe(8) bond length is 3.09 Å. Both Sm(1)-Fe(1) bond lengths are 3.02 Å. There is one shorter (3.20 Å) and one longer (3.23 Å) Sm(1)-Fe(10) bond length. Both Sm(1)-Fe(2) bond lengths are 3.04 Å. Both Sm(1)-Fe(3) bond lengths are 3.00 Å. Both Sm(1)-Fe(4) bond lengths are 3.28 Å. All Sm(1)-Fe(9) bond lengths are 3.22 Å. Both Sm(1)-Co(1) bond lengths are 3.11 Å. In the second Sm site, Sm(2) is bonded in a 19-coordinate geometry to one Fe(10), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(8), two equivalent Fe(9), and four equivalent Co(1) atoms. The Sm(2)-Fe(10) bond length is 3.07 Å. The Sm(2)-Fe(5) bond length is 3.28 Å. The Sm(2)-Fe(7) bond length is 3.07 Å. Both Sm(2)-Fe(1) bond lengths are 3.00 Å. Both Sm(2)-Fe(2) bond lengths are 3.03 Å. Both Sm(2)-Fe(3) bond lengths are 3.03 Å. Both Sm(2)-Fe(4) bond lengths are 3.29 Å. There is one shorter (3.18 Å) and one longer (3.24 Å) Sm(2)-Fe(8) bond length. Both Sm(2)-Fe(9) bond lengths are 3.09 Å. There are two shorter (3.21 Å) and two longer (3.24 Å) Sm(2)-Co(1) bond lengths. There are ten inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(1), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(8), two equivalent Fe(9), and one Co(1) atom. The Fe(1)-Fe(1) bond length is 2.50 Å. The Fe(1)-Fe(2) bond length is 2.48 Å. The Fe(1)-Fe(4) bond length is 2.44 Å. The Fe(1)-Fe(5) bond length is 2.45 Å. The Fe(1)-Fe(6) bond length is 2.77 Å. The Fe(1)-Fe(7) bond length is 2.75 Å. The Fe(1)-Fe(8) bond length is 2.55 Å. There is one shorter (2.54 Å) and one longer (2.64 Å) Fe(1)-Fe(9) bond length. The Fe(1)-Co(1) bond length is 2.65 Å. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(1), one Fe(10), one Fe(3), one Fe(6), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(4), and one Co(1) atom. The Fe(2)-Fe(10) bond length is 2.67 Å. The Fe(2)-Fe(3) bond length is 2.47 Å. The Fe(2)-Fe(6) bond length is 2.74 Å. The Fe(2)-Fe(7) bond length is 2.74 Å. The Fe(2)-Fe(8) bond length is 2.65 Å. The Fe(2)-Fe(9) bond length is 2.53 Å. Both Fe(2)-Fe(4) bond lengths are 2.44 Å. The Fe(2)-Co(1) bond length is 2.53 Å. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Sm(1), one Sm(2), one Fe(10), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(9), and two equivalent Co(1) atoms. The Fe(3)-Fe(10) bond length is 2.54 Å. The Fe(3)-Fe(3) bond length is 2.48 Å. The Fe(3)-Fe(4) bond length is 2.45 Å. The Fe(3)-Fe(5) bond length is 2.45 Å. The Fe(3)-Fe(6) bond length is 2.76 Å. The Fe(3)-Fe(7) bond length is 2.76 Å. The Fe(3)-Fe(9) bond length is 2.65 Å. There is one shorter (2.53 Å) and one longer (2.66 Å) Fe(3)-Co(1) bond length. In the fourth Fe site, Fe(4) is bonded to one Sm(1), one Sm(2), one Fe(1), one Fe(10), one Fe(3), one Fe(6), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(2), and one Co(1) atom to form distorted FeSm2Fe9Co cuboctahedra that share  a cornercorner with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a cornercorner with one Fe(8)Sm3Fe9 cuboctahedra, corners with two equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with four equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with four equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra. The Fe(4)-Fe(10) bond length is 2.46 Å. The Fe(4)-Fe(6) bond length is 2.60 Å. The Fe(4)-Fe(7) bond length is 2.61 Å. The Fe(4)-Fe(8) bond length is 2.46 Å. The Fe(4)-Fe(9) bond length is 2.45 Å. The Fe(4)-Co(1) bond length is 2.44 Å. In the fifth Fe site, Fe(5) is bonded to one Sm(1), one Sm(2), one Fe(6), one Fe(7), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(9), and two equivalent Co(1) atoms to form distorted FeSm2Fe8Co2 cuboctahedra that share corners with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with two equivalent Co(1)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with three equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, faces with two equivalent Co(1)Sm3Fe9 cuboctahedra, and faces with four equivalent Fe(4)Sm2Fe9Co cuboctahedra. The Fe(5)-Fe(6) bond length is 2.60 Å. The Fe(5)-Fe(7) bond length is 2.60 Å. Both Fe(5)-Fe(9) bond lengths are 2.46 Å. Both Fe(5)-Co(1) bond lengths are 2.44 Å. In the sixth Fe site, Fe(6) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(10), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Fe(9) atoms. The Fe(6)-Fe(10) bond length is 2.67 Å. The Fe(6)-Fe(7) bond length is 2.40 Å. Both Fe(6)-Fe(9) bond lengths are 2.65 Å. In the seventh Fe site, Fe(7) is bonded in a 14-coordinate geometry to one Sm(2), one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Co(1) atoms. The Fe(7)-Fe(8) bond length is 2.62 Å. Both Fe(7)-Co(1) bond lengths are 2.63 Å. In the eighth Fe site, Fe(8) is bonded to one Sm(1), two equivalent Sm(2), one Fe(7), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and two equivalent Fe(9) atoms to form FeSm3Fe9 cuboctahedra that share corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with two equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with six equivalent Fe(9)Sm3Fe8Co cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(10)Sm3Fe7Co2 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with four equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with four equivalent Co(1)Sm3Fe9 cuboctahedra. Both Fe(8)-Fe(9) bond lengths are 2.48 Å. In the ninth Fe site, Fe(9) is bonded to one Sm(2), two equivalent Sm(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(8), two equivalent Fe(1), and one Co(1) atom to form FeSm3Fe8Co cuboctahedra that share  a cornercorner with one Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, corners with three equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with five equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Co(1)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, edges with two equivalent Fe(9)Sm3Fe8Co cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra. The Fe(9)-Co(1) bond length is 2.45 Å. In the tenth Fe site, Fe(10) is bonded to one Sm(2), two equivalent Sm(1), one Fe(6), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Co(1) atoms to form FeSm3Fe7Co2 cuboctahedra that share corners with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with two equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with two equivalent Fe(8)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(5)Sm2Fe8Co2 cuboctahedra, corners with six equivalent Co(1)Sm3Fe9 cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with four equivalent Fe(9)Sm3Fe8Co cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(8)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Co(1)Sm3Fe9 cuboctahedra, and faces with four equivalent Fe(9)Sm3Fe8Co cuboctahedra. Both Fe(10)-Co(1) bond lengths are 2.47 Å. Co(1) is bonded to one Sm(1), two equivalent Sm(2), one Fe(1), one Fe(10), one Fe(2), one Fe(4), one Fe(5), one Fe(7), one Fe(9), and two equivalent Fe(3) atoms to form distorted CoSm3Fe9 cuboctahedra that share  a cornercorner with one Fe(5)Sm2Fe8Co2 cuboctahedra, corners with two equivalent Co(1)Sm3Fe9 cuboctahedra, corners with three equivalent Fe(10)Sm3Fe7Co2 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe9Co cuboctahedra, corners with five equivalent Fe(9)Sm3Fe8Co cuboctahedra,  an edgeedge with one Fe(5)Sm2Fe8Co2 cuboctahedra,  an edgeedge with one Fe(9)Sm3Fe8Co cuboctahedra, edges with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, edges with two equivalent Fe(8)Sm3Fe9 cuboctahedra, edges with two equivalent Co(1)Sm3Fe9 cuboctahedra,  a faceface with one Fe(5)Sm2Fe8Co2 cuboctahedra,  a faceface with one Fe(10)Sm3Fe7Co2 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe9Co cuboctahedra, faces with two equivalent Fe(9)Sm3Fe8Co cuboctahedra, faces with two equivalent Fe(8)Sm3Fe9 cuboctahedra, and faces with two equivalent Co(1)Sm3Fe9 cuboctahedra.