SmNdFe4Co13 is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the trigonal R3m space group. Sm(1) is bonded in a 19-coordinate geometry to one Fe(2), three equivalent Fe(1), three equivalent Co(3), six equivalent Co(1), and six equivalent Co(2) atoms. Nd(1) is bonded in a 19-coordinate geometry to three equivalent Fe(1), one Co(4), three equivalent Co(2), six equivalent Co(1), and six equivalent Co(3) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Sm(1), one Nd(1), one Fe(2), one Co(4), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form distorted FeNdSmFeCo9 cuboctahedra that share corners with four equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with five equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, corners with five equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, edges with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, edges with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, faces with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, faces with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, and faces with four equivalent Fe(1)NdSmFeCo9 cuboctahedra. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Sm(1), three equivalent Fe(1), one Co(4), three equivalent Co(2), and six equivalent Co(1) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 12-coordinate geometry to one Sm(1), one Nd(1), one Fe(2), two equivalent Fe(1), one Co(4), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(3) atoms. In the second Co site, Co(2) is bonded to two equivalent Sm(1), one Nd(1), one Fe(2), two equivalent Fe(1), two equivalent Co(3), and four equivalent Co(1) atoms to form CoNdSm2Fe3Co6 cuboctahedra that share corners with two equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, corners with five equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with eight equivalent Co(3)Nd2SmFe2Co7 cuboctahedra,  an edgeedge with one Co(3)Nd2SmFe2Co7 cuboctahedra, edges with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, edges with four equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, faces with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, faces with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, and faces with four equivalent Co(2)NdSm2Fe3Co6 cuboctahedra. In the third Co site, Co(3) is bonded to one Sm(1), two equivalent Nd(1), two equivalent Fe(1), one Co(4), two equivalent Co(2), and four equivalent Co(1) atoms to form CoNd2SmFe2Co7 cuboctahedra that share corners with two equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, corners with five equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with eight equivalent Co(2)NdSm2Fe3Co6 cuboctahedra,  an edgeedge with one Co(2)NdSm2Fe3Co6 cuboctahedra, edges with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, edges with four equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, faces with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, faces with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, and faces with four equivalent Co(3)Nd2SmFe2Co7 cuboctahedra. In the fourth Co site, Co(4) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(2), three equivalent Fe(1), three equivalent Co(3), and six equivalent Co(1) atoms.
SmNdFe4Co13 is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the trigonal R3m space group. Sm(1) is bonded in a 19-coordinate geometry to one Fe(2), three equivalent Fe(1), three equivalent Co(3), six equivalent Co(1), and six equivalent Co(2) atoms. The Sm(1)-Fe(2) bond length is 3.08 Å. All Sm(1)-Fe(1) bond lengths are 3.28 Å. All Sm(1)-Co(3) bond lengths are 3.02 Å. All Sm(1)-Co(1) bond lengths are 3.02 Å. There are three shorter (3.15 Å) and three longer (3.20 Å) Sm(1)-Co(2) bond lengths. Nd(1) is bonded in a 19-coordinate geometry to three equivalent Fe(1), one Co(4), three equivalent Co(2), six equivalent Co(1), and six equivalent Co(3) atoms. All Nd(1)-Fe(1) bond lengths are 3.24 Å. The Nd(1)-Co(4) bond length is 3.05 Å. All Nd(1)-Co(2) bond lengths are 3.03 Å. All Nd(1)-Co(1) bond lengths are 3.03 Å. There are three shorter (3.17 Å) and three longer (3.18 Å) Nd(1)-Co(3) bond lengths. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Sm(1), one Nd(1), one Fe(2), one Co(4), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form distorted FeNdSmFeCo9 cuboctahedra that share corners with four equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with five equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, corners with five equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, edges with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, edges with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, faces with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, faces with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, and faces with four equivalent Fe(1)NdSmFeCo9 cuboctahedra. The Fe(1)-Fe(2) bond length is 2.62 Å. The Fe(1)-Co(4) bond length is 2.55 Å. Both Fe(1)-Co(2) bond lengths are 2.44 Å. Both Fe(1)-Co(3) bond lengths are 2.42 Å. There are two shorter (2.39 Å) and two longer (2.41 Å) Fe(1)-Co(1) bond lengths. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Sm(1), three equivalent Fe(1), one Co(4), three equivalent Co(2), and six equivalent Co(1) atoms. The Fe(2)-Co(4) bond length is 2.31 Å. All Fe(2)-Co(2) bond lengths are 2.63 Å. All Fe(2)-Co(1) bond lengths are 2.66 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 12-coordinate geometry to one Sm(1), one Nd(1), one Fe(2), two equivalent Fe(1), one Co(4), two equivalent Co(1), two equivalent Co(2), and two equivalent Co(3) atoms. The Co(1)-Co(4) bond length is 2.68 Å. There is one shorter (2.40 Å) and one longer (2.41 Å) Co(1)-Co(1) bond length. There is one shorter (2.52 Å) and one longer (2.63 Å) Co(1)-Co(2) bond length. There is one shorter (2.51 Å) and one longer (2.64 Å) Co(1)-Co(3) bond length. In the second Co site, Co(2) is bonded to two equivalent Sm(1), one Nd(1), one Fe(2), two equivalent Fe(1), two equivalent Co(3), and four equivalent Co(1) atoms to form CoNdSm2Fe3Co6 cuboctahedra that share corners with two equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, corners with five equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with eight equivalent Co(3)Nd2SmFe2Co7 cuboctahedra,  an edgeedge with one Co(3)Nd2SmFe2Co7 cuboctahedra, edges with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, edges with four equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, faces with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, faces with three equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, and faces with four equivalent Co(2)NdSm2Fe3Co6 cuboctahedra. Both Co(2)-Co(3) bond lengths are 2.45 Å. In the third Co site, Co(3) is bonded to one Sm(1), two equivalent Nd(1), two equivalent Fe(1), one Co(4), two equivalent Co(2), and four equivalent Co(1) atoms to form CoNd2SmFe2Co7 cuboctahedra that share corners with two equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, corners with five equivalent Fe(1)NdSmFeCo9 cuboctahedra, corners with eight equivalent Co(2)NdSm2Fe3Co6 cuboctahedra,  an edgeedge with one Co(2)NdSm2Fe3Co6 cuboctahedra, edges with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, edges with four equivalent Co(3)Nd2SmFe2Co7 cuboctahedra, faces with three equivalent Fe(1)NdSmFeCo9 cuboctahedra, faces with three equivalent Co(2)NdSm2Fe3Co6 cuboctahedra, and faces with four equivalent Co(3)Nd2SmFe2Co7 cuboctahedra. The Co(3)-Co(4) bond length is 2.63 Å. In the fourth Co site, Co(4) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(2), three equivalent Fe(1), three equivalent Co(3), and six equivalent Co(1) atoms.