The structure described by Dy2Fe15Si2C crystallizes in the monoclinic C2/m space group. Dy(1) is bonded in a distorted single-bond geometry to one Fe(3), two equivalent Fe(4), four equivalent Fe(6), six equivalent Fe(2), one Si(1), and one C(1) atom. There are six 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), one Si(1), and one C(1) atom. In the second Fe site, Fe(2) is bonded to three equivalent Dy(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), three equivalent Fe(6), and one Si(1) atom to form FeDy3Fe8Si cuboctahedra that share  a cornercorner with one Fe(3)Dy2Fe8Si2 cuboctahedra, corners with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with seven equivalent Fe(2)Dy3Fe8Si cuboctahedra, corners with two equivalent C(1)Dy2Fe4 octahedra,  an edgeedge with one Fe(3)Dy2Fe8Si2 cuboctahedra, edges with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, edges with three equivalent Fe(2)Dy3Fe8Si cuboctahedra,  a faceface with one Fe(3)Dy2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, and  a faceface with one C(1)Dy2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-71°. In the third Fe site, Fe(3) is bonded to two equivalent Dy(1), four equivalent Fe(2), four equivalent Fe(6), and two equivalent Si(1) atoms to form distorted FeDy2Fe8Si2 cuboctahedra that share corners with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, corners with two equivalent C(1)Dy2Fe4 octahedra, edges with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra. The corner-sharing octahedral tilt angles are 47°. In the fourth Fe site, Fe(4) is bonded to two equivalent Dy(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Si(1) atoms to form distorted FeDy2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with eight equivalent Fe(2)Dy3Fe8Si cuboctahedra, edges with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, and faces with two equivalent C(1)Dy2Fe4 octahedra. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), two equivalent Si(1), and one C(1) atom. In the sixth Fe site, Fe(6) is bonded in a 12-coordinate geometry to two equivalent Dy(1), one Fe(1), one Fe(3), one Fe(4), one Fe(5), one Fe(6), three equivalent Fe(2), and two equivalent Si(1) atoms. Si(1) is bonded in a 14-coordinate geometry to one Dy(1), one Fe(1), one Fe(3), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(6), and one Si(1) atom. C(1) is bonded to two equivalent Dy(1), two equivalent Fe(1), and two equivalent Fe(5) atoms to form CDy2Fe4 octahedra that share corners with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, corners with eight equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Fe15Si2C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.424
_cell_length_b   6.424
_cell_length_c   6.408
_cell_angle_alpha   82.262
_cell_angle_beta   82.262
_cell_angle_gamma   81.951
_symmetry_Int_Tables_number   1
_cell_volume   257.669
_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
  Dy  Dy0  1  0.344  0.344  0.352  1.0
  Dy  Dy1  1  0.656  0.656  0.648  1.0
  Fe  Fe2  1  0.655  0.655  0.149  1.0
  Fe  Fe3  1  0.662  0.153  0.659  1.0
  Fe  Fe4  1  0.153  0.662  0.659  1.0
  Fe  Fe5  1  0.345  0.345  0.851  1.0
  Fe  Fe6  1  0.338  0.847  0.341  1.0
  Fe  Fe7  1  0.847  0.338  0.341  1.0
  Fe  Fe8  1  0.000  0.000  0.500  1.0
  Fe  Fe9  1  0.000  0.500  0.000  1.0
  Fe  Fe10  1  0.500  0.000  0.000  1.0
  Fe  Fe11  1  0.720  0.280  0.000  1.0
  Fe  Fe12  1  0.302  0.003  0.698  1.0
  Fe  Fe13  1  0.997  0.698  0.302  1.0
  Fe  Fe14  1  0.698  0.997  0.302  1.0
  Fe  Fe15  1  0.003  0.302  0.698  1.0
  Fe  Fe16  1  0.280  0.720  0.000  1.0
  Si  Si17  1  0.102  0.102  0.100  1.0
  Si  Si18  1  0.898  0.898  0.900  1.0
  C  C19  1  0.500  0.500  0.000  1.0
[/CIF]
.
The structure described by Dy2Fe15Si2C crystallizes in the monoclinic C2/m space group. Dy(1) is bonded in a distorted single-bond geometry to one Fe(3), two equivalent Fe(4), four equivalent Fe(6), six equivalent Fe(2), one Si(1), and one C(1) atom. There are six 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), one Si(1), and one C(1) atom. In the second Fe site, Fe(2) is bonded to three equivalent Dy(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(5), three equivalent Fe(6), and one Si(1) atom to form FeDy3Fe8Si cuboctahedra that share  a cornercorner with one Fe(3)Dy2Fe8Si2 cuboctahedra, corners with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with seven equivalent Fe(2)Dy3Fe8Si cuboctahedra, corners with two equivalent C(1)Dy2Fe4 octahedra,  an edgeedge with one Fe(3)Dy2Fe8Si2 cuboctahedra, edges with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, edges with three equivalent Fe(2)Dy3Fe8Si cuboctahedra,  a faceface with one Fe(3)Dy2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, and  a faceface with one C(1)Dy2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-71°. In the third Fe site, Fe(3) is bonded to two equivalent Dy(1), four equivalent Fe(2), four equivalent Fe(6), and two equivalent Si(1) atoms to form distorted FeDy2Fe8Si2 cuboctahedra that share corners with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, corners with two equivalent C(1)Dy2Fe4 octahedra, edges with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra. The corner-sharing octahedral tilt angles are 47°. In the fourth Fe site, Fe(4) is bonded to two equivalent Dy(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Si(1) atoms to form distorted FeDy2Fe8Si2 cuboctahedra that share corners with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, corners with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, corners with eight equivalent Fe(2)Dy3Fe8Si cuboctahedra, edges with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, faces with two equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra, and faces with two equivalent C(1)Dy2Fe4 octahedra. In the fifth Fe site, Fe(5) is bonded in a single-bond geometry to two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(6), two equivalent Si(1), and one C(1) atom. In the sixth Fe site, Fe(6) is bonded in a 12-coordinate geometry to two equivalent Dy(1), one Fe(1), one Fe(3), one Fe(4), one Fe(5), one Fe(6), three equivalent Fe(2), and two equivalent Si(1) atoms. Si(1) is bonded in a 14-coordinate geometry to one Dy(1), one Fe(1), one Fe(3), two equivalent Fe(2), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(6), and one Si(1) atom. C(1) is bonded to two equivalent Dy(1), two equivalent Fe(1), and two equivalent Fe(5) atoms to form CDy2Fe4 octahedra that share corners with two equivalent Fe(3)Dy2Fe8Si2 cuboctahedra, corners with eight equivalent Fe(2)Dy3Fe8Si cuboctahedra, faces with four equivalent Fe(4)Dy2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Dy3Fe8Si cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Fe15Si2C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.424
_cell_length_b   6.424
_cell_length_c   6.408
_cell_angle_alpha   82.262
_cell_angle_beta   82.262
_cell_angle_gamma   81.951
_symmetry_Int_Tables_number   1
_cell_volume   257.669
_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
  Dy  Dy0  1  0.344  0.344  0.352  1.0
  Dy  Dy1  1  0.656  0.656  0.648  1.0
  Fe  Fe2  1  0.655  0.655  0.149  1.0
  Fe  Fe3  1  0.662  0.153  0.659  1.0
  Fe  Fe4  1  0.153  0.662  0.659  1.0
  Fe  Fe5  1  0.345  0.345  0.851  1.0
  Fe  Fe6  1  0.338  0.847  0.341  1.0
  Fe  Fe7  1  0.847  0.338  0.341  1.0
  Fe  Fe8  1  0.000  0.000  0.500  1.0
  Fe  Fe9  1  0.000  0.500  0.000  1.0
  Fe  Fe10  1  0.500  0.000  0.000  1.0
  Fe  Fe11  1  0.720  0.280  0.000  1.0
  Fe  Fe12  1  0.302  0.003  0.698  1.0
  Fe  Fe13  1  0.997  0.698  0.302  1.0
  Fe  Fe14  1  0.698  0.997  0.302  1.0
  Fe  Fe15  1  0.003  0.302  0.698  1.0
  Fe  Fe16  1  0.280  0.720  0.000  1.0
  Si  Si17  1  0.102  0.102  0.100  1.0
  Si  Si18  1  0.898  0.898  0.900  1.0
  C  C19  1  0.500  0.500  0.000  1.0
[/CIF]
.