Er3SmFe34 crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 20-coordinate geometry to two equivalent Fe(2), six equivalent Fe(4), six equivalent Fe(5), and six equivalent Fe(6) atoms. In the second Er site, Er(2) is bonded in a 18-coordinate geometry to six equivalent Fe(3), six equivalent Fe(4), and six equivalent Fe(6) atoms. In the third Er site, Er(3) is bonded in a 18-coordinate geometry to six equivalent Fe(3), six equivalent Fe(4), and six equivalent Fe(7) atoms. Sm(1) is bonded in a 20-coordinate geometry to two equivalent Fe(1), six equivalent Fe(3), six equivalent Fe(5), and six equivalent Fe(7) atoms. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(1), three equivalent Fe(3), three equivalent Fe(5), and six equivalent Fe(6) atoms. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Er(1), one Fe(2), three equivalent Fe(4), three equivalent Fe(5), and six equivalent Fe(7) atoms. In the third Fe site, Fe(7) is bonded in a 12-coordinate geometry to one Er(3), one Sm(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(7) atoms. In the fourth Fe site, Fe(3) is bonded to one Er(2), one Er(3), one Sm(1), one Fe(1), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSmEr2Fe9 cuboctahedra that share corners with four equivalent Fe(4)Er3Fe9 cuboctahedra, corners with five equivalent Fe(5)SmErFe10 cuboctahedra, corners with six equivalent Fe(3)SmEr2Fe9 cuboctahedra, edges with three equivalent Fe(5)SmErFe10 cuboctahedra, edges with five equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(5)SmErFe10 cuboctahedra, and faces with six equivalent Fe(3)SmEr2Fe9 cuboctahedra. In the fifth Fe site, Fe(4) is bonded to one Er(1), one Er(2), one Er(3), one Fe(2), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form distorted FeEr3Fe9 cuboctahedra that share corners with four equivalent Fe(3)SmEr2Fe9 cuboctahedra, corners with five equivalent Fe(5)SmErFe10 cuboctahedra, corners with six equivalent Fe(4)Er3Fe9 cuboctahedra, edges with three equivalent Fe(5)SmErFe10 cuboctahedra, edges with five equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(5)SmErFe10 cuboctahedra, and faces with six equivalent Fe(4)Er3Fe9 cuboctahedra. In the sixth Fe site, Fe(5) is bonded to one Er(1), one Sm(1), one Fe(1), one Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSmErFe10 cuboctahedra that share corners with four equivalent Fe(5)SmErFe10 cuboctahedra, corners with five equivalent Fe(4)Er3Fe9 cuboctahedra, corners with five equivalent Fe(3)SmEr2Fe9 cuboctahedra, edges with three equivalent Fe(4)Er3Fe9 cuboctahedra, edges with three equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(3)SmEr2Fe9 cuboctahedra, and faces with six equivalent Fe(5)SmErFe10 cuboctahedra. In the seventh Fe site, Fe(6) is bonded in a 12-coordinate geometry to one Er(1), one Er(2), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(6) atoms.
Er3SmFe34 crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 20-coordinate geometry to two equivalent Fe(2), six equivalent Fe(4), six equivalent Fe(5), and six equivalent Fe(6) atoms. Both Er(1)-Fe(2) bond lengths are 2.95 Å. All Er(1)-Fe(4) bond lengths are 3.13 Å. All Er(1)-Fe(5) bond lengths are 3.18 Å. All Er(1)-Fe(6) bond lengths are 2.98 Å. In the second Er site, Er(2) is bonded in a 18-coordinate geometry to six equivalent Fe(3), six equivalent Fe(4), and six equivalent Fe(6) atoms. All Er(2)-Fe(3) bond lengths are 3.24 Å. All Er(2)-Fe(4) bond lengths are 3.12 Å. All Er(2)-Fe(6) bond lengths are 2.93 Å. In the third Er site, Er(3) is bonded in a 18-coordinate geometry to six equivalent Fe(3), six equivalent Fe(4), and six equivalent Fe(7) atoms. All Er(3)-Fe(3) bond lengths are 3.11 Å. All Er(3)-Fe(4) bond lengths are 3.26 Å. All Er(3)-Fe(7) bond lengths are 2.93 Å. Sm(1) is bonded in a 20-coordinate geometry to two equivalent Fe(1), six equivalent Fe(3), six equivalent Fe(5), and six equivalent Fe(7) atoms. Both Sm(1)-Fe(1) bond lengths are 2.96 Å. All Sm(1)-Fe(3) bond lengths are 3.15 Å. All Sm(1)-Fe(5) bond lengths are 3.20 Å. All Sm(1)-Fe(7) bond lengths are 2.99 Å. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Sm(1), one Fe(1), three equivalent Fe(3), three equivalent Fe(5), and six equivalent Fe(6) atoms. The Fe(1)-Fe(1) bond length is 2.34 Å. All Fe(1)-Fe(3) bond lengths are 2.65 Å. All Fe(1)-Fe(5) bond lengths are 2.60 Å. All Fe(1)-Fe(6) bond lengths are 2.80 Å. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Er(1), one Fe(2), three equivalent Fe(4), three equivalent Fe(5), and six equivalent Fe(7) atoms. The Fe(2)-Fe(2) bond length is 2.35 Å. All Fe(2)-Fe(4) bond lengths are 2.64 Å. All Fe(2)-Fe(5) bond lengths are 2.58 Å. All Fe(2)-Fe(7) bond lengths are 2.79 Å. In the third Fe site, Fe(7) is bonded in a 12-coordinate geometry to one Er(3), one Sm(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(7) atoms. Both Fe(7)-Fe(3) bond lengths are 2.60 Å. Both Fe(7)-Fe(4) bond lengths are 2.51 Å. Both Fe(7)-Fe(5) bond lengths are 2.46 Å. There is one shorter (2.47 Å) and one longer (2.59 Å) Fe(7)-Fe(7) bond length. In the fourth Fe site, Fe(3) is bonded to one Er(2), one Er(3), one Sm(1), one Fe(1), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSmEr2Fe9 cuboctahedra that share corners with four equivalent Fe(4)Er3Fe9 cuboctahedra, corners with five equivalent Fe(5)SmErFe10 cuboctahedra, corners with six equivalent Fe(3)SmEr2Fe9 cuboctahedra, edges with three equivalent Fe(5)SmErFe10 cuboctahedra, edges with five equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(5)SmErFe10 cuboctahedra, and faces with six equivalent Fe(3)SmEr2Fe9 cuboctahedra. Both Fe(3)-Fe(4) bond lengths are 2.43 Å. Both Fe(3)-Fe(5) bond lengths are 2.45 Å. Both Fe(3)-Fe(6) bond lengths are 2.51 Å. In the fifth Fe site, Fe(4) is bonded to one Er(1), one Er(2), one Er(3), one Fe(2), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form distorted FeEr3Fe9 cuboctahedra that share corners with four equivalent Fe(3)SmEr2Fe9 cuboctahedra, corners with five equivalent Fe(5)SmErFe10 cuboctahedra, corners with six equivalent Fe(4)Er3Fe9 cuboctahedra, edges with three equivalent Fe(5)SmErFe10 cuboctahedra, edges with five equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(5)SmErFe10 cuboctahedra, and faces with six equivalent Fe(4)Er3Fe9 cuboctahedra. Both Fe(4)-Fe(5) bond lengths are 2.44 Å. Both Fe(4)-Fe(6) bond lengths are 2.58 Å. In the sixth Fe site, Fe(5) is bonded to one Er(1), one Sm(1), one Fe(1), one Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(6), and two equivalent Fe(7) atoms to form FeSmErFe10 cuboctahedra that share corners with four equivalent Fe(5)SmErFe10 cuboctahedra, corners with five equivalent Fe(4)Er3Fe9 cuboctahedra, corners with five equivalent Fe(3)SmEr2Fe9 cuboctahedra, edges with three equivalent Fe(4)Er3Fe9 cuboctahedra, edges with three equivalent Fe(3)SmEr2Fe9 cuboctahedra, faces with two equivalent Fe(4)Er3Fe9 cuboctahedra, faces with two equivalent Fe(3)SmEr2Fe9 cuboctahedra, and faces with six equivalent Fe(5)SmErFe10 cuboctahedra. Both Fe(5)-Fe(6) bond lengths are 2.44 Å. In the seventh Fe site, Fe(6) is bonded in a 12-coordinate geometry to one Er(1), one Er(2), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), and two equivalent Fe(6) atoms. There is one shorter (2.49 Å) and one longer (2.59 Å) Fe(6)-Fe(6) bond length.