Sm2Fe17N crystallizes in the monoclinic C2/m space group. Sm(1) is bonded in a distorted single-bond geometry to one Fe(3), one Fe(7), two equivalent Fe(4), four equivalent Fe(2), six equivalent Fe(6), and one N(1) atom. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a single-bond geometry to two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), two equivalent Fe(7), and one N(1) atom. In the second Fe site, Fe(2) is bonded to two equivalent Sm(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), two equivalent Fe(7), and three equivalent Fe(6) atoms to form distorted FeSm2Fe10 cuboctahedra that share  a cornercorner with one Fe(3)Sm2Fe10 cuboctahedra, corners with three equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with five equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with seven equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra,  an edgeedge with one Fe(2)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(3)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(4)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Sm3Fe9 cuboctahedra,  an edgeedge with one N(1)Sm2Fe4 octahedra,  a faceface with one Fe(3)Sm2Fe10 cuboctahedra, faces with three equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(2)Sm2Fe10 cuboctahedra, and faces with seven equivalent Fe(6)Sm3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles range from 24-30°. In the third Fe site, Fe(3) is bonded to two equivalent Sm(1), two equivalent Fe(7), four equivalent Fe(2), and four equivalent Fe(6) atoms to form distorted FeSm2Fe10 cuboctahedra that share corners with four equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra, edges with four equivalent Fe(2)Sm2Fe10 cuboctahedra, edges with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with four equivalent Fe(2)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(4)Sm2Fe10 cuboctahedra, and faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. In the fourth Fe site, Fe(4) is bonded to two equivalent Sm(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSm2Fe10 cuboctahedra that share corners with two equivalent Fe(3)Sm2Fe10 cuboctahedra, corners with two equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with six equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(6)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(2)Sm2Fe10 cuboctahedra, edges with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(3)Sm2Fe10 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with six equivalent Fe(2)Sm2Fe10 cuboctahedra, and faces with two equivalent N(1)Sm2Fe4 octahedra. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to one Fe(7), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), and one N(1) atom. In the sixth Fe site, Fe(6) is bonded to three equivalent Sm(1), one Fe(1), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), and three equivalent Fe(2) atoms to form FeSm3Fe9 cuboctahedra that share  a cornercorner with one Fe(3)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with five equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with seven equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra,  an edgeedge with one Fe(2)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(3)Sm2Fe10 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe10 cuboctahedra, edges with three equivalent Fe(6)Sm3Fe9 cuboctahedra,  a faceface with one Fe(3)Sm2Fe10 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with seven equivalent Fe(2)Sm2Fe10 cuboctahedra, and  a faceface with one N(1)Sm2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-69°. In the seventh Fe site, Fe(7) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(3), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(4), two equivalent Fe(6), and four equivalent Fe(2) atoms. N(1) is bonded to two equivalent Sm(1), two equivalent Fe(1), and two equivalent Fe(5) atoms to form NSm2Fe4 octahedra that share corners with two equivalent Fe(3)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(6)Sm3Fe9 cuboctahedra, edges with four equivalent Fe(2)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(4)Sm2Fe10 cuboctahedra, and faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra.
Sm2Fe17N crystallizes in the monoclinic C2/m space group. Sm(1) is bonded in a distorted single-bond geometry to one Fe(3), one Fe(7), two equivalent Fe(4), four equivalent Fe(2), six equivalent Fe(6), and one N(1) atom. The Sm(1)-Fe(3) bond length is 3.31 Å. The Sm(1)-Fe(7) bond length is 3.05 Å. Both Sm(1)-Fe(4) bond lengths are 3.31 Å. There are two shorter (3.08 Å) and two longer (3.11 Å) Sm(1)-Fe(2) bond lengths. There are a spread of Sm(1)-Fe(6) bond distances ranging from 3.08-3.30 Å. The Sm(1)-N(1) bond length is 2.49 Å. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a single-bond geometry to two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), two equivalent Fe(7), and one N(1) atom. Both Fe(1)-Fe(2) bond lengths are 2.46 Å. Both Fe(1)-Fe(4) bond lengths are 2.43 Å. Both Fe(1)-Fe(6) bond lengths are 2.57 Å. Both Fe(1)-Fe(7) bond lengths are 2.73 Å. The Fe(1)-N(1) bond length is 1.87 Å. In the second Fe site, Fe(2) is bonded to two equivalent Sm(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), two equivalent Fe(7), and three equivalent Fe(6) atoms to form distorted FeSm2Fe10 cuboctahedra that share  a cornercorner with one Fe(3)Sm2Fe10 cuboctahedra, corners with three equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with five equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with seven equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra,  an edgeedge with one Fe(2)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(3)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(4)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Sm3Fe9 cuboctahedra,  an edgeedge with one N(1)Sm2Fe4 octahedra,  a faceface with one Fe(3)Sm2Fe10 cuboctahedra, faces with three equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(2)Sm2Fe10 cuboctahedra, and faces with seven equivalent Fe(6)Sm3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles range from 24-30°. The Fe(2)-Fe(2) bond length is 2.46 Å. The Fe(2)-Fe(3) bond length is 2.42 Å. The Fe(2)-Fe(4) bond length is 2.43 Å. The Fe(2)-Fe(5) bond length is 2.54 Å. There is one shorter (2.73 Å) and one longer (2.74 Å) Fe(2)-Fe(7) bond length. There are a spread of Fe(2)-Fe(6) bond distances ranging from 2.57-2.65 Å. In the third Fe site, Fe(3) is bonded to two equivalent Sm(1), two equivalent Fe(7), four equivalent Fe(2), and four equivalent Fe(6) atoms to form distorted FeSm2Fe10 cuboctahedra that share corners with four equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra, edges with four equivalent Fe(2)Sm2Fe10 cuboctahedra, edges with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with four equivalent Fe(2)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(4)Sm2Fe10 cuboctahedra, and faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. Both Fe(3)-Fe(7) bond lengths are 2.61 Å. All Fe(3)-Fe(6) bond lengths are 2.47 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent Sm(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSm2Fe10 cuboctahedra that share corners with two equivalent Fe(3)Sm2Fe10 cuboctahedra, corners with two equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with six equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(6)Sm3Fe9 cuboctahedra, edges with two equivalent Fe(2)Sm2Fe10 cuboctahedra, edges with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with two equivalent Fe(3)Sm2Fe10 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with six equivalent Fe(2)Sm2Fe10 cuboctahedra, and faces with two equivalent N(1)Sm2Fe4 octahedra. Both Fe(4)-Fe(5) bond lengths are 2.47 Å. Both Fe(4)-Fe(6) bond lengths are 2.47 Å. Both Fe(4)-Fe(7) bond lengths are 2.64 Å. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to one Fe(7), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), and one N(1) atom. The Fe(5)-Fe(7) bond length is 2.65 Å. Both Fe(5)-Fe(6) bond lengths are 2.56 Å. The Fe(5)-N(1) bond length is 1.93 Å. In the sixth Fe site, Fe(6) is bonded to three equivalent Sm(1), one Fe(1), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), and three equivalent Fe(2) atoms to form FeSm3Fe9 cuboctahedra that share  a cornercorner with one Fe(3)Sm2Fe10 cuboctahedra, corners with four equivalent Fe(4)Sm2Fe10 cuboctahedra, corners with five equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with seven equivalent Fe(6)Sm3Fe9 cuboctahedra, corners with two equivalent N(1)Sm2Fe4 octahedra,  an edgeedge with one Fe(2)Sm2Fe10 cuboctahedra,  an edgeedge with one Fe(3)Sm2Fe10 cuboctahedra, edges with two equivalent Fe(4)Sm2Fe10 cuboctahedra, edges with three equivalent Fe(6)Sm3Fe9 cuboctahedra,  a faceface with one Fe(3)Sm2Fe10 cuboctahedra, faces with two equivalent Fe(4)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra, faces with seven equivalent Fe(2)Sm2Fe10 cuboctahedra, and  a faceface with one N(1)Sm2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-69°. The Fe(6)-Fe(6) bond length is 2.53 Å. The Fe(6)-Fe(7) bond length is 2.65 Å. In the seventh Fe site, Fe(7) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(3), one Fe(5), one Fe(7), two equivalent Fe(1), two equivalent Fe(4), two equivalent Fe(6), and four equivalent Fe(2) atoms. The Fe(7)-Fe(7) bond length is 2.40 Å. N(1) is bonded to two equivalent Sm(1), two equivalent Fe(1), and two equivalent Fe(5) atoms to form NSm2Fe4 octahedra that share corners with two equivalent Fe(3)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Sm2Fe10 cuboctahedra, corners with eight equivalent Fe(6)Sm3Fe9 cuboctahedra, edges with four equivalent Fe(2)Sm2Fe10 cuboctahedra, faces with four equivalent Fe(4)Sm2Fe10 cuboctahedra, and faces with four equivalent Fe(6)Sm3Fe9 cuboctahedra.