The material described by Ce3Co8Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 12-coordinate geometry to three equivalent Co(3) and nine equivalent Co(1) atoms. In the second Ce site, Ce(2) is bonded in a 18-coordinate geometry to three equivalent Co(2), twelve equivalent Co(1), and three equivalent Si(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Ce(2), three equivalent Ce(1), one Co(2), one Co(3), four equivalent Co(1), and one Si(1) atom to form CoCe5Co6Si cuboctahedra that share corners with two equivalent Co(2)Ce3Co6 cuboctahedra, corners with two equivalent Co(3)Ce6Co6 cuboctahedra, corners with two equivalent Si(1)Ce3Co6 cuboctahedra, corners with fifteen equivalent Co(1)Ce5Co6Si cuboctahedra, edges with two equivalent Co(2)Ce3Co6 cuboctahedra, edges with two equivalent Si(1)Ce3Co6 cuboctahedra, edges with eight equivalent Co(1)Ce5Co6Si cuboctahedra,  a faceface with one Co(2)Ce3Co6 cuboctahedra,  a faceface with one Si(1)Ce3Co6 cuboctahedra, faces with three equivalent Co(3)Ce6Co6 cuboctahedra, and faces with eleven equivalent Co(1)Ce5Co6Si cuboctahedra. In the second Co site, Co(2) is bonded to three equivalent Ce(2) and six equivalent Co(1) atoms to form distorted CoCe3Co6 cuboctahedra that share corners with three equivalent Si(1)Ce3Co6 cuboctahedra, corners with six equivalent Co(2)Ce3Co6 cuboctahedra, corners with six equivalent Co(3)Ce6Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, faces with three equivalent Si(1)Ce3Co6 cuboctahedra, and faces with six equivalent Co(1)Ce5Co6Si cuboctahedra. In the third Co site, Co(3) is bonded to six equivalent Ce(1) and six equivalent Co(1) atoms to form CoCe6Co6 cuboctahedra that share corners with six equivalent Co(2)Ce3Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with six equivalent Co(3)Ce6Co6 cuboctahedra, faces with two equivalent Si(1)Ce3Co6 cuboctahedra, and faces with eighteen equivalent Co(1)Ce5Co6Si cuboctahedra. Si(1) is bonded to three equivalent Ce(2) and six equivalent Co(1) atoms to form distorted SiCe3Co6 cuboctahedra that share corners with three equivalent Co(2)Ce3Co6 cuboctahedra, corners with six equivalent Si(1)Ce3Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, faces with two equivalent Co(3)Ce6Co6 cuboctahedra, faces with three equivalent Co(2)Ce3Co6 cuboctahedra, and faces with six equivalent Co(1)Ce5Co6Si cuboctahedra. is represented by the CIF file [CIF]
data_Ce3Co8Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   4.980
_cell_length_c   15.812
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.652
_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  0.333  0.667  0.960  1.0
  Ce  Ce1  1  0.667  0.333  0.040  1.0
  Ce  Ce2  1  0.667  0.333  0.460  1.0
  Ce  Ce3  1  0.333  0.667  0.540  1.0
  Ce  Ce4  1  0.333  0.667  0.750  1.0
  Ce  Ce5  1  0.667  0.333  0.250  1.0
  Co  Co6  1  0.166  0.834  0.370  1.0
  Co  Co7  1  0.166  0.333  0.370  1.0
  Co  Co8  1  0.667  0.834  0.370  1.0
  Co  Co9  1  0.834  0.166  0.630  1.0
  Co  Co10  1  0.834  0.667  0.630  1.0
  Co  Co11  1  0.333  0.166  0.630  1.0
  Co  Co12  1  0.834  0.166  0.870  1.0
  Co  Co13  1  0.834  0.667  0.870  1.0
  Co  Co14  1  0.333  0.166  0.870  1.0
  Co  Co15  1  0.166  0.834  0.130  1.0
  Co  Co16  1  0.166  0.333  0.130  1.0
  Co  Co17  1  0.667  0.834  0.130  1.0
  Co  Co18  1  0.333  0.667  0.250  1.0
  Co  Co19  1  0.667  0.333  0.750  1.0
  Co  Co20  1  0.000  0.000  0.500  1.0
  Co  Co21  1  0.000  0.000  0.000  1.0
  Si  Si22  1  0.000  0.000  0.250  1.0
  Si  Si23  1  0.000  0.000  0.750  1.0
[/CIF]
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The material described by Ce3Co8Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 12-coordinate geometry to three equivalent Co(3) and nine equivalent Co(1) atoms. In the second Ce site, Ce(2) is bonded in a 18-coordinate geometry to three equivalent Co(2), twelve equivalent Co(1), and three equivalent Si(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Ce(2), three equivalent Ce(1), one Co(2), one Co(3), four equivalent Co(1), and one Si(1) atom to form CoCe5Co6Si cuboctahedra that share corners with two equivalent Co(2)Ce3Co6 cuboctahedra, corners with two equivalent Co(3)Ce6Co6 cuboctahedra, corners with two equivalent Si(1)Ce3Co6 cuboctahedra, corners with fifteen equivalent Co(1)Ce5Co6Si cuboctahedra, edges with two equivalent Co(2)Ce3Co6 cuboctahedra, edges with two equivalent Si(1)Ce3Co6 cuboctahedra, edges with eight equivalent Co(1)Ce5Co6Si cuboctahedra,  a faceface with one Co(2)Ce3Co6 cuboctahedra,  a faceface with one Si(1)Ce3Co6 cuboctahedra, faces with three equivalent Co(3)Ce6Co6 cuboctahedra, and faces with eleven equivalent Co(1)Ce5Co6Si cuboctahedra. In the second Co site, Co(2) is bonded to three equivalent Ce(2) and six equivalent Co(1) atoms to form distorted CoCe3Co6 cuboctahedra that share corners with three equivalent Si(1)Ce3Co6 cuboctahedra, corners with six equivalent Co(2)Ce3Co6 cuboctahedra, corners with six equivalent Co(3)Ce6Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, faces with three equivalent Si(1)Ce3Co6 cuboctahedra, and faces with six equivalent Co(1)Ce5Co6Si cuboctahedra. In the third Co site, Co(3) is bonded to six equivalent Ce(1) and six equivalent Co(1) atoms to form CoCe6Co6 cuboctahedra that share corners with six equivalent Co(2)Ce3Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with six equivalent Co(3)Ce6Co6 cuboctahedra, faces with two equivalent Si(1)Ce3Co6 cuboctahedra, and faces with eighteen equivalent Co(1)Ce5Co6Si cuboctahedra. Si(1) is bonded to three equivalent Ce(2) and six equivalent Co(1) atoms to form distorted SiCe3Co6 cuboctahedra that share corners with three equivalent Co(2)Ce3Co6 cuboctahedra, corners with six equivalent Si(1)Ce3Co6 cuboctahedra, corners with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, edges with twelve equivalent Co(1)Ce5Co6Si cuboctahedra, faces with two equivalent Co(3)Ce6Co6 cuboctahedra, faces with three equivalent Co(2)Ce3Co6 cuboctahedra, and faces with six equivalent Co(1)Ce5Co6Si cuboctahedra. is represented by the CIF file [CIF]
data_Ce3Co8Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   4.980
_cell_length_c   15.812
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.652
_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  0.333  0.667  0.960  1.0
  Ce  Ce1  1  0.667  0.333  0.040  1.0
  Ce  Ce2  1  0.667  0.333  0.460  1.0
  Ce  Ce3  1  0.333  0.667  0.540  1.0
  Ce  Ce4  1  0.333  0.667  0.750  1.0
  Ce  Ce5  1  0.667  0.333  0.250  1.0
  Co  Co6  1  0.166  0.834  0.370  1.0
  Co  Co7  1  0.166  0.333  0.370  1.0
  Co  Co8  1  0.667  0.834  0.370  1.0
  Co  Co9  1  0.834  0.166  0.630  1.0
  Co  Co10  1  0.834  0.667  0.630  1.0
  Co  Co11  1  0.333  0.166  0.630  1.0
  Co  Co12  1  0.834  0.166  0.870  1.0
  Co  Co13  1  0.834  0.667  0.870  1.0
  Co  Co14  1  0.333  0.166  0.870  1.0
  Co  Co15  1  0.166  0.834  0.130  1.0
  Co  Co16  1  0.166  0.333  0.130  1.0
  Co  Co17  1  0.667  0.834  0.130  1.0
  Co  Co18  1  0.333  0.667  0.250  1.0
  Co  Co19  1  0.667  0.333  0.750  1.0
  Co  Co20  1  0.000  0.000  0.500  1.0
  Co  Co21  1  0.000  0.000  0.000  1.0
  Si  Si22  1  0.000  0.000  0.250  1.0
  Si  Si23  1  0.000  0.000  0.750  1.0
[/CIF]
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