The compound described by CeNi9Si4 crystallizes in the tetragonal I4/mcm space group. Ce(1) is bonded in a 24-coordinate geometry to eight equivalent Ni(1), eight equivalent Ni(2), and eight equivalent Si(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Ce(1), one Ni(3), two equivalent Ni(2), three equivalent Ni(1), and four equivalent Si(1) atoms to form NiCe2Si4Ni6 cuboctahedra that share  a cornercorner with one Ni(3)Si4Ni8 cuboctahedra, corners with eleven equivalent Ni(1)Ce2Si4Ni6 cuboctahedra, faces with two equivalent Ni(3)Si4Ni8 cuboctahedra, and faces with seven equivalent Ni(1)Ce2Si4Ni6 cuboctahedra. In the second Ni site, Ni(2) is bonded in a 11-coordinate geometry to two equivalent Ce(1), one Ni(3), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Si(1) atoms. In the third Ni site, Ni(3) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Si(1) atoms to form a mixture of corner and face-sharing NiSi4Ni8 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Ni(3), four equivalent Ni(1), four equivalent Ni(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSi4Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.954
_cell_length_b   7.954
_cell_length_c   7.954
_cell_angle_alpha   121.026
_cell_angle_beta   121.026
_cell_angle_gamma   88.232
_symmetry_Int_Tables_number   1
_cell_volume   350.127
_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  0.000  1.0
  Ce  Ce1  1  0.250  0.250  0.000  1.0
  Si  Si2  1  0.446  0.946  0.159  1.0
  Si  Si3  1  0.212  0.712  0.159  1.0
  Si  Si4  1  0.712  0.554  0.500  1.0
  Si  Si5  1  0.946  0.788  0.500  1.0
  Si  Si6  1  0.288  0.446  0.500  1.0
  Si  Si7  1  0.788  0.288  0.841  1.0
  Si  Si8  1  0.554  0.054  0.841  1.0
  Si  Si9  1  0.054  0.212  0.500  1.0
  Ni  Ni10  1  0.569  0.704  0.273  1.0
  Ni  Ni11  1  0.796  0.931  0.727  1.0
  Ni  Ni12  1  0.318  0.818  0.764  1.0
  Ni  Ni13  1  0.818  0.054  0.500  1.0
  Ni  Ni14  1  0.431  0.296  0.727  1.0
  Ni  Ni15  1  0.182  0.946  0.500  1.0
  Ni  Ni16  1  0.446  0.682  0.500  1.0
  Ni  Ni17  1  0.946  0.446  0.764  1.0
  Ni  Ni18  1  0.682  0.182  0.236  1.0
  Ni  Ni19  1  0.054  0.554  0.236  1.0
  Ni  Ni20  1  0.500  0.000  0.500  1.0
  Ni  Ni21  1  0.000  0.500  0.500  1.0
  Ni  Ni22  1  0.296  0.569  0.865  1.0
  Ni  Ni23  1  0.931  0.204  0.135  1.0
  Ni  Ni24  1  0.069  0.796  0.865  1.0
  Ni  Ni25  1  0.204  0.069  0.273  1.0
  Ni  Ni26  1  0.554  0.318  0.500  1.0
  Ni  Ni27  1  0.704  0.431  0.135  1.0
[/CIF]
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The compound described by CeNi9Si4 crystallizes in the tetragonal I4/mcm space group. Ce(1) is bonded in a 24-coordinate geometry to eight equivalent Ni(1), eight equivalent Ni(2), and eight equivalent Si(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Ce(1), one Ni(3), two equivalent Ni(2), three equivalent Ni(1), and four equivalent Si(1) atoms to form NiCe2Si4Ni6 cuboctahedra that share  a cornercorner with one Ni(3)Si4Ni8 cuboctahedra, corners with eleven equivalent Ni(1)Ce2Si4Ni6 cuboctahedra, faces with two equivalent Ni(3)Si4Ni8 cuboctahedra, and faces with seven equivalent Ni(1)Ce2Si4Ni6 cuboctahedra. In the second Ni site, Ni(2) is bonded in a 11-coordinate geometry to two equivalent Ce(1), one Ni(3), two equivalent Ni(1), two equivalent Ni(2), and four equivalent Si(1) atoms. In the third Ni site, Ni(3) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Si(1) atoms to form a mixture of corner and face-sharing NiSi4Ni8 cuboctahedra. Si(1) is bonded in a 12-coordinate geometry to two equivalent Ce(1), one Ni(3), four equivalent Ni(1), four equivalent Ni(2), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeSi4Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.954
_cell_length_b   7.954
_cell_length_c   7.954
_cell_angle_alpha   121.026
_cell_angle_beta   121.026
_cell_angle_gamma   88.232
_symmetry_Int_Tables_number   1
_cell_volume   350.127
_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  0.000  1.0
  Ce  Ce1  1  0.250  0.250  0.000  1.0
  Si  Si2  1  0.446  0.946  0.159  1.0
  Si  Si3  1  0.212  0.712  0.159  1.0
  Si  Si4  1  0.712  0.554  0.500  1.0
  Si  Si5  1  0.946  0.788  0.500  1.0
  Si  Si6  1  0.288  0.446  0.500  1.0
  Si  Si7  1  0.788  0.288  0.841  1.0
  Si  Si8  1  0.554  0.054  0.841  1.0
  Si  Si9  1  0.054  0.212  0.500  1.0
  Ni  Ni10  1  0.569  0.704  0.273  1.0
  Ni  Ni11  1  0.796  0.931  0.727  1.0
  Ni  Ni12  1  0.318  0.818  0.764  1.0
  Ni  Ni13  1  0.818  0.054  0.500  1.0
  Ni  Ni14  1  0.431  0.296  0.727  1.0
  Ni  Ni15  1  0.182  0.946  0.500  1.0
  Ni  Ni16  1  0.446  0.682  0.500  1.0
  Ni  Ni17  1  0.946  0.446  0.764  1.0
  Ni  Ni18  1  0.682  0.182  0.236  1.0
  Ni  Ni19  1  0.054  0.554  0.236  1.0
  Ni  Ni20  1  0.500  0.000  0.500  1.0
  Ni  Ni21  1  0.000  0.500  0.500  1.0
  Ni  Ni22  1  0.296  0.569  0.865  1.0
  Ni  Ni23  1  0.931  0.204  0.135  1.0
  Ni  Ni24  1  0.069  0.796  0.865  1.0
  Ni  Ni25  1  0.204  0.069  0.273  1.0
  Ni  Ni26  1  0.554  0.318  0.500  1.0
  Ni  Ni27  1  0.704  0.431  0.135  1.0
[/CIF]
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