The material structure described by Er4Fe34C3 crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted bent 120 degrees geometry to one Fe(1), one Fe(15), one Fe(17), one Fe(18), two equivalent Fe(13), three equivalent Fe(7), one C(1), and one C(2) atom. In the second Er site, Er(2) is bonded in a distorted single-bond geometry to one Fe(16), one Fe(17), one Fe(18), one Fe(2), two equivalent Fe(12), two equivalent Fe(14), three equivalent Fe(6), three equivalent Fe(8), and one C(1) atom. There are eighteen inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Er(1), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(15), one Fe(17), one Fe(18), one Fe(2), one Fe(4), one Fe(5), one Fe(7), and one Fe(9) atom. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Er(2), one Fe(1), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(16), one Fe(17), one Fe(18), one Fe(3), one Fe(6), one Fe(8), and one Fe(9) atom. In the third Fe site, Fe(3) is bonded in a single-bond geometry to one Fe(13), one Fe(17), one Fe(18), one Fe(2), one Fe(7), and one C(1) atom. In the fourth Fe site, Fe(4) is bonded in a single-bond geometry to one Fe(1), one Fe(12), one Fe(14), one Fe(17), one Fe(18), one Fe(6), one Fe(8), and one C(1) atom. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to one Fe(1), one Fe(13), one Fe(15), one Fe(18), one Fe(7), and one C(2) atom. In the sixth Fe site, Fe(6) is bonded to three equivalent Er(2), one Fe(14), one Fe(16), one Fe(18), one Fe(2), one Fe(4), one Fe(8), one Fe(9), and two equivalent Fe(12) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(18)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with three equivalent Fe(17)Er2Fe10 cuboctahedra, corners with three equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra, edges with two equivalent Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra, faces with three equivalent Fe(14)Er2Fe10 cuboctahedra, faces with three equivalent Fe(8)Er3Fe9 cuboctahedra, and  a faceface with one C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 66-70°. In the seventh Fe site, Fe(7) is bonded to three equivalent Er(1), one Fe(1), one Fe(11), one Fe(15), one Fe(17), one Fe(3), one Fe(5), one Fe(9), and two equivalent Fe(13) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(6)Er3Fe9 cuboctahedra,  a cornercorner with one Fe(8)Er3Fe9 cuboctahedra, corners with three equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, corners with two equivalent C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(15)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one C(1)Er2Fe4 octahedra, and  a faceface with one C(2)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 63-69°. In the eighth Fe site, Fe(8) is bonded to three equivalent Er(2), one Fe(10), one Fe(12), one Fe(16), one Fe(17), one Fe(2), one Fe(4), one Fe(6), and two equivalent Fe(14) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with three equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra, edges with two equivalent Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with three equivalent Fe(14)Er2Fe10 cuboctahedra, faces with three equivalent Fe(6)Er3Fe9 cuboctahedra, and  a faceface with one C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-69°. In the ninth Fe site, Fe(9) is bonded in a single-bond geometry to one Fe(1), one Fe(14), one Fe(17), one Fe(18), one Fe(2), one Fe(6), one Fe(7), and one C(1) atom. In the tenth Fe site, Fe(10) is bonded in a single-bond geometry to one Fe(1), one Fe(12), one Fe(13), one Fe(17), one Fe(18), one Fe(2), one Fe(8), and one C(1) atom. In the eleventh Fe site, Fe(11) is bonded in a single-bond geometry to one Fe(1), one Fe(13), one Fe(15), one Fe(18), one Fe(2), one Fe(7), and one C(2) atom. In the twelfth Fe site, Fe(12) is bonded in a 12-coordinate geometry to two equivalent Er(2), one Fe(1), one Fe(10), one Fe(14), one Fe(16), one Fe(18), one Fe(2), one Fe(4), one Fe(8), and two equivalent Fe(6) atoms. In the thirteenth Fe site, Fe(13) is bonded in a 12-coordinate geometry to two equivalent Er(1), one Fe(1), one Fe(10), one Fe(11), one Fe(15), one Fe(17), one Fe(2), one Fe(3), one Fe(5), and two equivalent Fe(7) atoms. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Er(2), one Fe(1), one Fe(12), one Fe(16), one Fe(17), one Fe(2), one Fe(4), one Fe(6), one Fe(9), and two equivalent Fe(8) atoms to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(14)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one C(1)Er2Fe4 octahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with three equivalent Fe(6)Er3Fe9 cuboctahedra, and faces with three equivalent Fe(8)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles range from 25-30°. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Er(1), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(13), two equivalent Fe(5), and two equivalent Fe(7) atoms to form FeEr2Fe10 cuboctahedra that share corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, edges with two equivalent Fe(7)Er3Fe9 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with two equivalent Fe(7)Er3Fe9 cuboctahedra, and faces with two equivalent C(2)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Er(2), two equivalent Fe(12), two equivalent Fe(14), two equivalent Fe(2), two equivalent Fe(6), and two equivalent Fe(8) atoms to form FeEr2Fe10 cuboctahedra that share corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, edges with two equivalent Fe(14)Er2Fe10 cuboctahedra, edges with two equivalent Fe(6)Er3Fe9 cuboctahedra, edges with two equivalent Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(14)Er2Fe10 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with two equivalent Fe(6)Er3Fe9 cuboctahedra, and faces with two equivalent Fe(8)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. In the seventeenth Fe site, Fe(17) is bonded to one Er(1), one Er(2), one Fe(1), one Fe(10), one Fe(13), one Fe(14), one Fe(2), one Fe(3), one Fe(4), one Fe(7), one Fe(8), and one Fe(9) atom to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(14)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra,  a cornercorner with one Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(6)Er3Fe9 cuboctahedra,  a cornercorner with one C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, and faces with two equivalent C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles are 44°. In the eighteenth Fe site, Fe(18) is bonded to one Er(1), one Er(2), one Fe(1), one Fe(10), one Fe(11), one Fe(12), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), and one Fe(9) atom to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with three equivalent Fe(7)Er3Fe9 cuboctahedra, corners with three equivalent Fe(8)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(14)Er2Fe10 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra,  a faceface with one C(2)Er2Fe4 octahedra, and faces with two equivalent C(1)Er2Fe4 octahedra. There are two inequivalent C sites. In the first C site, C(1) is bonded to one Er(1), one Er(2), one Fe(10), one Fe(3), one Fe(4), and one Fe(9) atom to form CEr2Fe4 octahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra,  a cornercorner with one C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, and faces with two equivalent Fe(18)Er2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 62°. In the second C site, C(2) is bonded to two equivalent Er(1), two equivalent Fe(11), and two equivalent Fe(5) atoms to form CEr2Fe4 octahedra that share corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with four equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, faces with two equivalent Fe(15)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, and faces with two equivalent Fe(7)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er4Fe34C3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.475
_cell_length_b   6.441
_cell_length_c   12.902
_cell_angle_alpha   82.986
_cell_angle_beta   83.469
_cell_angle_gamma   83.542
_symmetry_Int_Tables_number   1
_cell_volume   527.930
_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
  Er  Er0  1  0.664  0.654  0.328  1.0
  Er  Er1  1  0.661  0.660  0.826  1.0
  Er  Er2  1  0.336  0.346  0.172  1.0
  Er  Er3  1  0.339  0.340  0.674  1.0
  Fe  Fe4  1  0.902  0.904  0.452  1.0
  Fe  Fe5  1  0.905  0.904  0.951  1.0
  Fe  Fe6  1  0.098  0.096  0.048  1.0
  Fe  Fe7  1  0.095  0.096  0.549  1.0
  Fe  Fe8  1  0.342  0.345  0.426  1.0
  Fe  Fe9  1  0.343  0.343  0.924  1.0
  Fe  Fe10  1  0.342  0.851  0.172  1.0
  Fe  Fe11  1  0.344  0.850  0.673  1.0
  Fe  Fe12  1  0.853  0.345  0.173  1.0
  Fe  Fe13  1  0.849  0.345  0.673  1.0
  Fe  Fe14  1  0.658  0.655  0.074  1.0
  Fe  Fe15  1  0.657  0.657  0.576  1.0
  Fe  Fe16  1  0.658  0.149  0.328  1.0
  Fe  Fe17  1  0.656  0.150  0.827  1.0
  Fe  Fe18  1  0.147  0.655  0.327  1.0
  Fe  Fe19  1  0.151  0.655  0.827  1.0
  Fe  Fe20  1  0.285  0.716  0.500  1.0
  Fe  Fe21  1  0.284  0.715  1.000  1.0
  Fe  Fe22  1  0.716  1.000  0.142  1.0
  Fe  Fe23  1  0.709  0.000  0.647  1.0
  Fe  Fe24  1  0.001  0.291  0.355  1.0
  Fe  Fe25  1  0.999  0.291  0.854  1.0
  Fe  Fe26  1  0.284  0.000  0.358  1.0
  Fe  Fe27  1  0.291  1.000  0.853  1.0
  Fe  Fe28  1  0.999  0.709  0.145  1.0
  Fe  Fe29  1  0.001  0.709  0.646  1.0
  Fe  Fe30  1  0.715  0.284  1.000  1.0
  Fe  Fe31  1  0.716  0.285  0.500  1.0
  Fe  Fe32  1  0.000  0.000  0.250  1.0
  Fe  Fe33  1  0.000  0.000  0.750  1.0
  Fe  Fe34  1  0.999  0.500  0.500  1.0
  Fe  Fe35  1  0.001  0.500  1.000  1.0
  Fe  Fe36  1  0.500  0.998  0.999  1.0
  Fe  Fe37  1  0.500  0.002  0.501  1.0
  C  C38  1  0.499  0.500  1.000  1.0
  C  C39  1  0.501  0.500  0.500  1.0
  C  C40  1  0.500  0.000  0.250  1.0
[/CIF]
.
The material structure described by Er4Fe34C3 crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted bent 120 degrees geometry to one Fe(1), one Fe(15), one Fe(17), one Fe(18), two equivalent Fe(13), three equivalent Fe(7), one C(1), and one C(2) atom. In the second Er site, Er(2) is bonded in a distorted single-bond geometry to one Fe(16), one Fe(17), one Fe(18), one Fe(2), two equivalent Fe(12), two equivalent Fe(14), three equivalent Fe(6), three equivalent Fe(8), and one C(1) atom. There are eighteen inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Er(1), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(15), one Fe(17), one Fe(18), one Fe(2), one Fe(4), one Fe(5), one Fe(7), and one Fe(9) atom. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Er(2), one Fe(1), one Fe(10), one Fe(11), one Fe(12), one Fe(13), one Fe(14), one Fe(16), one Fe(17), one Fe(18), one Fe(3), one Fe(6), one Fe(8), and one Fe(9) atom. In the third Fe site, Fe(3) is bonded in a single-bond geometry to one Fe(13), one Fe(17), one Fe(18), one Fe(2), one Fe(7), and one C(1) atom. In the fourth Fe site, Fe(4) is bonded in a single-bond geometry to one Fe(1), one Fe(12), one Fe(14), one Fe(17), one Fe(18), one Fe(6), one Fe(8), and one C(1) atom. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to one Fe(1), one Fe(13), one Fe(15), one Fe(18), one Fe(7), and one C(2) atom. In the sixth Fe site, Fe(6) is bonded to three equivalent Er(2), one Fe(14), one Fe(16), one Fe(18), one Fe(2), one Fe(4), one Fe(8), one Fe(9), and two equivalent Fe(12) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(18)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with three equivalent Fe(17)Er2Fe10 cuboctahedra, corners with three equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra, edges with two equivalent Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra, faces with three equivalent Fe(14)Er2Fe10 cuboctahedra, faces with three equivalent Fe(8)Er3Fe9 cuboctahedra, and  a faceface with one C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 66-70°. In the seventh Fe site, Fe(7) is bonded to three equivalent Er(1), one Fe(1), one Fe(11), one Fe(15), one Fe(17), one Fe(3), one Fe(5), one Fe(9), and two equivalent Fe(13) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(6)Er3Fe9 cuboctahedra,  a cornercorner with one Fe(8)Er3Fe9 cuboctahedra, corners with three equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, corners with two equivalent C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(15)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one C(1)Er2Fe4 octahedra, and  a faceface with one C(2)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 63-69°. In the eighth Fe site, Fe(8) is bonded to three equivalent Er(2), one Fe(10), one Fe(12), one Fe(16), one Fe(17), one Fe(2), one Fe(4), one Fe(6), and two equivalent Fe(14) atoms to form FeEr3Fe9 cuboctahedra that share  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with three equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(18)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra, edges with two equivalent Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(18)Er2Fe10 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with three equivalent Fe(14)Er2Fe10 cuboctahedra, faces with three equivalent Fe(6)Er3Fe9 cuboctahedra, and  a faceface with one C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-69°. In the ninth Fe site, Fe(9) is bonded in a single-bond geometry to one Fe(1), one Fe(14), one Fe(17), one Fe(18), one Fe(2), one Fe(6), one Fe(7), and one C(1) atom. In the tenth Fe site, Fe(10) is bonded in a single-bond geometry to one Fe(1), one Fe(12), one Fe(13), one Fe(17), one Fe(18), one Fe(2), one Fe(8), and one C(1) atom. In the eleventh Fe site, Fe(11) is bonded in a single-bond geometry to one Fe(1), one Fe(13), one Fe(15), one Fe(18), one Fe(2), one Fe(7), and one C(2) atom. In the twelfth Fe site, Fe(12) is bonded in a 12-coordinate geometry to two equivalent Er(2), one Fe(1), one Fe(10), one Fe(14), one Fe(16), one Fe(18), one Fe(2), one Fe(4), one Fe(8), and two equivalent Fe(6) atoms. In the thirteenth Fe site, Fe(13) is bonded in a 12-coordinate geometry to two equivalent Er(1), one Fe(1), one Fe(10), one Fe(11), one Fe(15), one Fe(17), one Fe(2), one Fe(3), one Fe(5), and two equivalent Fe(7) atoms. In the fourteenth Fe site, Fe(14) is bonded to two equivalent Er(2), one Fe(1), one Fe(12), one Fe(16), one Fe(17), one Fe(2), one Fe(4), one Fe(6), one Fe(9), and two equivalent Fe(8) atoms to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(14)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra,  an edgeedge with one Fe(16)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(17)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one C(1)Er2Fe4 octahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(17)Er2Fe10 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with three equivalent Fe(6)Er3Fe9 cuboctahedra, and faces with three equivalent Fe(8)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles range from 25-30°. In the fifteenth Fe site, Fe(15) is bonded to two equivalent Er(1), two equivalent Fe(1), two equivalent Fe(11), two equivalent Fe(13), two equivalent Fe(5), and two equivalent Fe(7) atoms to form FeEr2Fe10 cuboctahedra that share corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, edges with two equivalent Fe(7)Er3Fe9 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with two equivalent Fe(7)Er3Fe9 cuboctahedra, and faces with two equivalent C(2)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. In the sixteenth Fe site, Fe(16) is bonded to two equivalent Er(2), two equivalent Fe(12), two equivalent Fe(14), two equivalent Fe(2), two equivalent Fe(6), and two equivalent Fe(8) atoms to form FeEr2Fe10 cuboctahedra that share corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, edges with two equivalent Fe(14)Er2Fe10 cuboctahedra, edges with two equivalent Fe(6)Er3Fe9 cuboctahedra, edges with two equivalent Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(14)Er2Fe10 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, faces with two equivalent Fe(6)Er3Fe9 cuboctahedra, and faces with two equivalent Fe(8)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 44°. In the seventeenth Fe site, Fe(17) is bonded to one Er(1), one Er(2), one Fe(1), one Fe(10), one Fe(13), one Fe(14), one Fe(2), one Fe(3), one Fe(4), one Fe(7), one Fe(8), and one Fe(9) atom to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(14)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(7)Er3Fe9 cuboctahedra,  a cornercorner with one Fe(8)Er3Fe9 cuboctahedra, corners with two equivalent Fe(18)Er2Fe10 cuboctahedra, corners with three equivalent Fe(6)Er3Fe9 cuboctahedra,  a cornercorner with one C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, and faces with two equivalent C(1)Er2Fe4 octahedra. The corner-sharing octahedral tilt angles are 44°. In the eighteenth Fe site, Fe(18) is bonded to one Er(1), one Er(2), one Fe(1), one Fe(10), one Fe(11), one Fe(12), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), and one Fe(9) atom to form distorted FeEr2Fe10 cuboctahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with three equivalent Fe(7)Er3Fe9 cuboctahedra, corners with three equivalent Fe(8)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(6)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(7)Er3Fe9 cuboctahedra,  an edgeedge with one Fe(8)Er3Fe9 cuboctahedra,  a faceface with one Fe(15)Er2Fe10 cuboctahedra,  a faceface with one Fe(16)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(14)Er2Fe10 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra,  a faceface with one C(2)Er2Fe4 octahedra, and faces with two equivalent C(1)Er2Fe4 octahedra. There are two inequivalent C sites. In the first C site, C(1) is bonded to one Er(1), one Er(2), one Fe(10), one Fe(3), one Fe(4), and one Fe(9) atom to form CEr2Fe4 octahedra that share  a cornercorner with one Fe(15)Er2Fe10 cuboctahedra,  a cornercorner with one Fe(16)Er2Fe10 cuboctahedra, corners with two equivalent Fe(14)Er2Fe10 cuboctahedra, corners with two equivalent Fe(6)Er3Fe9 cuboctahedra, corners with two equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent Fe(8)Er3Fe9 cuboctahedra,  a cornercorner with one C(2)Er2Fe4 octahedra,  an edgeedge with one Fe(14)Er2Fe10 cuboctahedra,  a faceface with one Fe(6)Er3Fe9 cuboctahedra,  a faceface with one Fe(7)Er3Fe9 cuboctahedra,  a faceface with one Fe(8)Er3Fe9 cuboctahedra, faces with two equivalent Fe(17)Er2Fe10 cuboctahedra, and faces with two equivalent Fe(18)Er2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 62°. In the second C site, C(2) is bonded to two equivalent Er(1), two equivalent Fe(11), and two equivalent Fe(5) atoms to form CEr2Fe4 octahedra that share corners with two equivalent Fe(17)Er2Fe10 cuboctahedra, corners with four equivalent Fe(7)Er3Fe9 cuboctahedra, corners with two equivalent C(1)Er2Fe4 octahedra, faces with two equivalent Fe(15)Er2Fe10 cuboctahedra, faces with two equivalent Fe(18)Er2Fe10 cuboctahedra, and faces with two equivalent Fe(7)Er3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er4Fe34C3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.475
_cell_length_b   6.441
_cell_length_c   12.902
_cell_angle_alpha   82.986
_cell_angle_beta   83.469
_cell_angle_gamma   83.542
_symmetry_Int_Tables_number   1
_cell_volume   527.930
_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
  Er  Er0  1  0.664  0.654  0.328  1.0
  Er  Er1  1  0.661  0.660  0.826  1.0
  Er  Er2  1  0.336  0.346  0.172  1.0
  Er  Er3  1  0.339  0.340  0.674  1.0
  Fe  Fe4  1  0.902  0.904  0.452  1.0
  Fe  Fe5  1  0.905  0.904  0.951  1.0
  Fe  Fe6  1  0.098  0.096  0.048  1.0
  Fe  Fe7  1  0.095  0.096  0.549  1.0
  Fe  Fe8  1  0.342  0.345  0.426  1.0
  Fe  Fe9  1  0.343  0.343  0.924  1.0
  Fe  Fe10  1  0.342  0.851  0.172  1.0
  Fe  Fe11  1  0.344  0.850  0.673  1.0
  Fe  Fe12  1  0.853  0.345  0.173  1.0
  Fe  Fe13  1  0.849  0.345  0.673  1.0
  Fe  Fe14  1  0.658  0.655  0.074  1.0
  Fe  Fe15  1  0.657  0.657  0.576  1.0
  Fe  Fe16  1  0.658  0.149  0.328  1.0
  Fe  Fe17  1  0.656  0.150  0.827  1.0
  Fe  Fe18  1  0.147  0.655  0.327  1.0
  Fe  Fe19  1  0.151  0.655  0.827  1.0
  Fe  Fe20  1  0.285  0.716  0.500  1.0
  Fe  Fe21  1  0.284  0.715  1.000  1.0
  Fe  Fe22  1  0.716  1.000  0.142  1.0
  Fe  Fe23  1  0.709  0.000  0.647  1.0
  Fe  Fe24  1  0.001  0.291  0.355  1.0
  Fe  Fe25  1  0.999  0.291  0.854  1.0
  Fe  Fe26  1  0.284  0.000  0.358  1.0
  Fe  Fe27  1  0.291  1.000  0.853  1.0
  Fe  Fe28  1  0.999  0.709  0.145  1.0
  Fe  Fe29  1  0.001  0.709  0.646  1.0
  Fe  Fe30  1  0.715  0.284  1.000  1.0
  Fe  Fe31  1  0.716  0.285  0.500  1.0
  Fe  Fe32  1  0.000  0.000  0.250  1.0
  Fe  Fe33  1  0.000  0.000  0.750  1.0
  Fe  Fe34  1  0.999  0.500  0.500  1.0
  Fe  Fe35  1  0.001  0.500  1.000  1.0
  Fe  Fe36  1  0.500  0.998  0.999  1.0
  Fe  Fe37  1  0.500  0.002  0.501  1.0
  C  C38  1  0.499  0.500  1.000  1.0
  C  C39  1  0.501  0.500  0.500  1.0
  C  C40  1  0.500  0.000  0.250  1.0
[/CIF]
.