The material described by Ce2Fe20Si2C crystallizes in the triclinic P-1 space group. Ce(1) is bonded in a distorted single-bond geometry to one Fe(10), one Fe(11), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(8), two equivalent Fe(9), and one C(1) atom. There are eleven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to two equivalent Ce(1), one Fe(10), one Fe(11), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(8), one Fe(9), one Si(1), and one Si(2) atom. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(11), one Fe(4), one Fe(5), one Fe(6), one Fe(8), one Fe(9), two equivalent Fe(3), and one Si(2) atom. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(4), one Fe(5), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(2), one Si(1), and one Si(2) atom. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(10), one Fe(2), one Fe(3), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(8), and one Si(1) atom. In the fifth Fe site, Fe(5) is bonded to two equivalent Ce(1), one Fe(1), one Fe(10), one Fe(11), one Fe(2), one Fe(3), one Fe(4), one Fe(6), one Fe(7), and two equivalent Fe(9) atoms to form distorted FeCe2Fe10 cuboctahedra that share  a cornercorner with one Fe(10)Ce2Fe10 cuboctahedra, corners with two equivalent Fe(5)Ce2Fe10 cuboctahedra, corners with two equivalent C(1)Ce2Fe4 octahedra,  an edgeedge with one C(1)Ce2Fe4 octahedra,  a faceface with one Fe(10)Ce2Fe10 cuboctahedra, and  a faceface with one Fe(5)Ce2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles range from 28-71°. In the sixth Fe site, Fe(6) is bonded in a single-bond geometry to one Fe(1), one Fe(10), one Fe(11), one Fe(2), one Fe(4), one Fe(5), one Fe(8), one Fe(9), and one C(1) atom. In the seventh Fe site, Fe(7) is bonded in a single-bond geometry to one Fe(1), one Fe(10), one Fe(3), one Fe(4), one Fe(5), one Fe(8), one Fe(9), one Si(1), and one C(1) atom. In the eighth Fe site, Fe(8) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(2), one Fe(3), one Fe(6), one Fe(7), one Fe(9), two equivalent Fe(4), one Si(1), and one Si(2) atom. In the ninth Fe site, Fe(9) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(11), one Fe(2), one Fe(3), one Fe(6), one Fe(7), one Fe(8), two equivalent Fe(5), and one Si(2) atom. In the tenth Fe site, Fe(10) is bonded to two equivalent Ce(1), two equivalent Fe(1), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form distorted FeCe2Fe10 cuboctahedra that share corners with two equivalent Fe(5)Ce2Fe10 cuboctahedra, faces with two equivalent Fe(5)Ce2Fe10 cuboctahedra, and faces with two equivalent C(1)Ce2Fe4 octahedra. In the eleventh Fe site, Fe(11) is bonded in a 12-coordinate geometry to two equivalent Ce(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(9) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(7), and two equivalent Fe(8) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(8), and two equivalent Fe(9) atoms. C(1) is bonded to two equivalent Ce(1), two equivalent Fe(6), and two equivalent Fe(7) atoms to form CCe2Fe4 octahedra that share corners with four equivalent Fe(5)Ce2Fe10 cuboctahedra, edges with two equivalent Fe(5)Ce2Fe10 cuboctahedra, and faces with two equivalent Fe(10)Ce2Fe10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce2Fe20Si2C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.368
_cell_length_b   7.762
_cell_length_c   7.776
_cell_angle_alpha   81.502
_cell_angle_beta   113.970
_cell_angle_gamma   114.202
_symmetry_Int_Tables_number   1
_cell_volume   320.266
_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
  Ce  Ce0  1  0.876  0.746  0.249  1.0
  Ce  Ce1  1  0.124  0.254  0.751  1.0
  Fe  Fe2  1  0.630  0.251  0.753  1.0
  Fe  Fe3  1  0.370  0.749  0.247  1.0
  Fe  Fe4  1  0.637  0.576  0.834  1.0
  Fe  Fe5  1  0.640  0.330  0.078  1.0
  Fe  Fe6  1  0.304  0.080  0.164  1.0
  Fe  Fe7  1  0.302  0.665  0.579  1.0
  Fe  Fe8  1  0.240  0.176  0.416  1.0
  Fe  Fe9  1  0.243  0.920  0.677  1.0
  Fe  Fe10  1  0.064  0.825  0.924  1.0
  Fe  Fe11  1  0.066  0.425  0.322  1.0
  Fe  Fe12  1  0.363  0.424  0.166  1.0
  Fe  Fe13  1  0.360  0.670  0.922  1.0
  Fe  Fe14  1  0.696  0.920  0.836  1.0
  Fe  Fe15  1  0.698  0.335  0.421  1.0
  Fe  Fe16  1  0.760  0.824  0.584  1.0
  Fe  Fe17  1  0.757  0.080  0.323  1.0
  Fe  Fe18  1  0.936  0.175  0.076  1.0
  Fe  Fe19  1  0.934  0.575  0.678  1.0
  Fe  Fe20  1  0.500  0.000  0.500  1.0
  Fe  Fe21  1  0.500  0.500  0.500  1.0
  Si  Si22  1  0.500  0.000  0.000  1.0
  Si  Si23  1  0.000  0.500  0.000  1.0
  C  C24  1  0.000  0.000  0.500  1.0
[/CIF]
.
The material described by Ce2Fe20Si2C crystallizes in the triclinic P-1 space group. Ce(1) is bonded in a distorted single-bond geometry to one Fe(10), one Fe(11), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(8), two equivalent Fe(9), and one C(1) atom. There are eleven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to two equivalent Ce(1), one Fe(10), one Fe(11), one Fe(2), one Fe(3), one Fe(4), one Fe(5), one Fe(6), one Fe(7), one Fe(8), one Fe(9), one Si(1), and one Si(2) atom. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(11), one Fe(4), one Fe(5), one Fe(6), one Fe(8), one Fe(9), two equivalent Fe(3), and one Si(2) atom. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(4), one Fe(5), one Fe(7), one Fe(8), one Fe(9), two equivalent Fe(2), one Si(1), and one Si(2) atom. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(10), one Fe(2), one Fe(3), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(8), and one Si(1) atom. In the fifth Fe site, Fe(5) is bonded to two equivalent Ce(1), one Fe(1), one Fe(10), one Fe(11), one Fe(2), one Fe(3), one Fe(4), one Fe(6), one Fe(7), and two equivalent Fe(9) atoms to form distorted FeCe2Fe10 cuboctahedra that share  a cornercorner with one Fe(10)Ce2Fe10 cuboctahedra, corners with two equivalent Fe(5)Ce2Fe10 cuboctahedra, corners with two equivalent C(1)Ce2Fe4 octahedra,  an edgeedge with one C(1)Ce2Fe4 octahedra,  a faceface with one Fe(10)Ce2Fe10 cuboctahedra, and  a faceface with one Fe(5)Ce2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles range from 28-71°. In the sixth Fe site, Fe(6) is bonded in a single-bond geometry to one Fe(1), one Fe(10), one Fe(11), one Fe(2), one Fe(4), one Fe(5), one Fe(8), one Fe(9), and one C(1) atom. In the seventh Fe site, Fe(7) is bonded in a single-bond geometry to one Fe(1), one Fe(10), one Fe(3), one Fe(4), one Fe(5), one Fe(8), one Fe(9), one Si(1), and one C(1) atom. In the eighth Fe site, Fe(8) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(2), one Fe(3), one Fe(6), one Fe(7), one Fe(9), two equivalent Fe(4), one Si(1), and one Si(2) atom. In the ninth Fe site, Fe(9) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(1), one Fe(11), one Fe(2), one Fe(3), one Fe(6), one Fe(7), one Fe(8), two equivalent Fe(5), and one Si(2) atom. In the tenth Fe site, Fe(10) is bonded to two equivalent Ce(1), two equivalent Fe(1), two equivalent Fe(4), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(7) atoms to form distorted FeCe2Fe10 cuboctahedra that share corners with two equivalent Fe(5)Ce2Fe10 cuboctahedra, faces with two equivalent Fe(5)Ce2Fe10 cuboctahedra, and faces with two equivalent C(1)Ce2Fe4 octahedra. In the eleventh Fe site, Fe(11) is bonded in a 12-coordinate geometry to two equivalent Ce(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), two equivalent Fe(6), and two equivalent Fe(9) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(7), and two equivalent Fe(8) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(8), and two equivalent Fe(9) atoms. C(1) is bonded to two equivalent Ce(1), two equivalent Fe(6), and two equivalent Fe(7) atoms to form CCe2Fe4 octahedra that share corners with four equivalent Fe(5)Ce2Fe10 cuboctahedra, edges with two equivalent Fe(5)Ce2Fe10 cuboctahedra, and faces with two equivalent Fe(10)Ce2Fe10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce2Fe20Si2C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.368
_cell_length_b   7.762
_cell_length_c   7.776
_cell_angle_alpha   81.502
_cell_angle_beta   113.970
_cell_angle_gamma   114.202
_symmetry_Int_Tables_number   1
_cell_volume   320.266
_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
  Ce  Ce0  1  0.876  0.746  0.249  1.0
  Ce  Ce1  1  0.124  0.254  0.751  1.0
  Fe  Fe2  1  0.630  0.251  0.753  1.0
  Fe  Fe3  1  0.370  0.749  0.247  1.0
  Fe  Fe4  1  0.637  0.576  0.834  1.0
  Fe  Fe5  1  0.640  0.330  0.078  1.0
  Fe  Fe6  1  0.304  0.080  0.164  1.0
  Fe  Fe7  1  0.302  0.665  0.579  1.0
  Fe  Fe8  1  0.240  0.176  0.416  1.0
  Fe  Fe9  1  0.243  0.920  0.677  1.0
  Fe  Fe10  1  0.064  0.825  0.924  1.0
  Fe  Fe11  1  0.066  0.425  0.322  1.0
  Fe  Fe12  1  0.363  0.424  0.166  1.0
  Fe  Fe13  1  0.360  0.670  0.922  1.0
  Fe  Fe14  1  0.696  0.920  0.836  1.0
  Fe  Fe15  1  0.698  0.335  0.421  1.0
  Fe  Fe16  1  0.760  0.824  0.584  1.0
  Fe  Fe17  1  0.757  0.080  0.323  1.0
  Fe  Fe18  1  0.936  0.175  0.076  1.0
  Fe  Fe19  1  0.934  0.575  0.678  1.0
  Fe  Fe20  1  0.500  0.000  0.500  1.0
  Fe  Fe21  1  0.500  0.500  0.500  1.0
  Si  Si22  1  0.500  0.000  0.000  1.0
  Si  Si23  1  0.000  0.500  0.000  1.0
  C  C24  1  0.000  0.000  0.500  1.0
[/CIF]
.