The compound described by CeFe9Si4 crystallizes in the tetragonal I4/mcm space group. Ce(1) is bonded in a 24-coordinate geometry to eight equivalent Fe(1), eight equivalent Fe(2), and eight equivalent Si(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Ce(1), one Fe(3), two equivalent Fe(2), three equivalent Fe(1), and four equivalent Si(1) atoms to form distorted FeCe2Fe6Si4 cuboctahedra that share  a cornercorner with one Fe(3)Fe8Si4 cuboctahedra, corners with eleven equivalent Fe(1)Ce2Fe6Si4 cuboctahedra, faces with two equivalent Fe(3)Fe8Si4 cuboctahedra, and faces with seven equivalent Fe(1)Ce2Fe6Si4 cuboctahedra. In the second Fe site, Fe(2) is bonded in a 4-coordinate geometry to two equivalent Ce(1), one Fe(3), two equivalent Fe(1), and four equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded to four equivalent Fe(1), four equivalent Fe(2), and four equivalent Si(1) atoms to form a mixture of corner and face-sharing FeFe8Si4 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(3), four equivalent Fe(1), four equivalent Fe(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_CeFe9Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.792
_cell_length_b   7.792
_cell_length_c   7.979
_cell_angle_alpha   119.229
_cell_angle_beta   119.229
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   350.363
_cell_formula_units_Z   2
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  0.750  0.750  0.500  1.0
  Ce  Ce1  1  0.250  0.250  0.500  1.0
  Fe  Fe2  1  0.299  0.567  0.000  1.0
  Fe  Fe3  1  0.701  0.433  0.000  1.0
  Fe  Fe4  1  0.201  0.067  0.000  1.0
  Fe  Fe5  1  0.799  0.933  0.000  1.0
  Fe  Fe6  1  0.433  0.299  0.000  1.0
  Fe  Fe7  1  0.567  0.701  0.000  1.0
  Fe  Fe8  1  0.933  0.201  0.000  1.0
  Fe  Fe9  1  0.067  0.799  0.000  1.0
  Fe  Fe10  1  0.555  0.303  0.358  1.0
  Fe  Fe11  1  0.803  0.055  0.358  1.0
  Fe  Fe12  1  0.303  0.803  0.358  1.0
  Fe  Fe13  1  0.055  0.555  0.358  1.0
  Fe  Fe14  1  0.445  0.697  0.642  1.0
  Fe  Fe15  1  0.197  0.945  0.642  1.0
  Fe  Fe16  1  0.697  0.197  0.642  1.0
  Fe  Fe17  1  0.945  0.445  0.642  1.0
  Fe  Fe18  1  0.000  0.500  0.000  1.0
  Fe  Fe19  1  0.500  0.000  0.000  1.0
  Si  Si20  1  0.950  0.792  0.242  1.0
  Si  Si21  1  0.292  0.450  0.242  1.0
  Si  Si22  1  0.792  0.292  0.242  1.0
  Si  Si23  1  0.450  0.950  0.242  1.0
  Si  Si24  1  0.050  0.208  0.758  1.0
  Si  Si25  1  0.708  0.550  0.758  1.0
  Si  Si26  1  0.208  0.708  0.758  1.0
  Si  Si27  1  0.550  0.050  0.758  1.0
[/CIF]
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The compound described by CeFe9Si4 crystallizes in the tetragonal I4/mcm space group. Ce(1) is bonded in a 24-coordinate geometry to eight equivalent Fe(1), eight equivalent Fe(2), and eight equivalent Si(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Ce(1), one Fe(3), two equivalent Fe(2), three equivalent Fe(1), and four equivalent Si(1) atoms to form distorted FeCe2Fe6Si4 cuboctahedra that share  a cornercorner with one Fe(3)Fe8Si4 cuboctahedra, corners with eleven equivalent Fe(1)Ce2Fe6Si4 cuboctahedra, faces with two equivalent Fe(3)Fe8Si4 cuboctahedra, and faces with seven equivalent Fe(1)Ce2Fe6Si4 cuboctahedra. In the second Fe site, Fe(2) is bonded in a 4-coordinate geometry to two equivalent Ce(1), one Fe(3), two equivalent Fe(1), and four equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded to four equivalent Fe(1), four equivalent Fe(2), and four equivalent Si(1) atoms to form a mixture of corner and face-sharing FeFe8Si4 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Fe(3), four equivalent Fe(1), four equivalent Fe(2), and one Si(1) atom. is represented by the CIF card [CIF]
data_CeFe9Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.792
_cell_length_b   7.792
_cell_length_c   7.979
_cell_angle_alpha   119.229
_cell_angle_beta   119.229
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   350.363
_cell_formula_units_Z   2
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  0.750  0.750  0.500  1.0
  Ce  Ce1  1  0.250  0.250  0.500  1.0
  Fe  Fe2  1  0.299  0.567  0.000  1.0
  Fe  Fe3  1  0.701  0.433  0.000  1.0
  Fe  Fe4  1  0.201  0.067  0.000  1.0
  Fe  Fe5  1  0.799  0.933  0.000  1.0
  Fe  Fe6  1  0.433  0.299  0.000  1.0
  Fe  Fe7  1  0.567  0.701  0.000  1.0
  Fe  Fe8  1  0.933  0.201  0.000  1.0
  Fe  Fe9  1  0.067  0.799  0.000  1.0
  Fe  Fe10  1  0.555  0.303  0.358  1.0
  Fe  Fe11  1  0.803  0.055  0.358  1.0
  Fe  Fe12  1  0.303  0.803  0.358  1.0
  Fe  Fe13  1  0.055  0.555  0.358  1.0
  Fe  Fe14  1  0.445  0.697  0.642  1.0
  Fe  Fe15  1  0.197  0.945  0.642  1.0
  Fe  Fe16  1  0.697  0.197  0.642  1.0
  Fe  Fe17  1  0.945  0.445  0.642  1.0
  Fe  Fe18  1  0.000  0.500  0.000  1.0
  Fe  Fe19  1  0.500  0.000  0.000  1.0
  Si  Si20  1  0.950  0.792  0.242  1.0
  Si  Si21  1  0.292  0.450  0.242  1.0
  Si  Si22  1  0.792  0.292  0.242  1.0
  Si  Si23  1  0.450  0.950  0.242  1.0
  Si  Si24  1  0.050  0.208  0.758  1.0
  Si  Si25  1  0.708  0.550  0.758  1.0
  Si  Si26  1  0.208  0.708  0.758  1.0
  Si  Si27  1  0.550  0.050  0.758  1.0
[/CIF]
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