The compound described by ThCeSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. Th(1) is bonded to four equivalent Si(1) and eight Si(2,2) atoms to form ThSi12 cuboctahedra that share edges with four equivalent Th(1)Si12 cuboctahedra, edges with eight equivalent Ce(1)Si12 cuboctahedra, faces with four equivalent Th(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. Ce(1) is bonded to four Si(2,2) and eight equivalent Si(1) atoms to form CeSi12 cuboctahedra that share edges with four equivalent Ce(1)Si12 cuboctahedra, edges with eight equivalent Th(1)Si12 cuboctahedra, faces with four equivalent Th(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Th(1), four equivalent Ce(1), one Si(1), and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. In the third Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. In the fourth Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_CeThSi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.696
_cell_length_b   7.696
_cell_length_c   7.696
_cell_angle_alpha   148.935
_cell_angle_beta   148.935
_cell_angle_gamma   44.506
_symmetry_Int_Tables_number   1
_cell_volume   120.996
_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  0.250  0.750  0.500  1.0
  Th  Th1  1  0.000  0.000  0.000  1.0
  Si  Si2  1  0.667  0.167  0.500  1.0
  Si  Si3  1  0.584  0.584  0.000  1.0
  Si  Si4  1  0.833  0.333  0.500  1.0
  Si  Si5  1  0.416  0.416  0.000  1.0
[/CIF]
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The compound described by ThCeSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. Th(1) is bonded to four equivalent Si(1) and eight Si(2,2) atoms to form ThSi12 cuboctahedra that share edges with four equivalent Th(1)Si12 cuboctahedra, edges with eight equivalent Ce(1)Si12 cuboctahedra, faces with four equivalent Th(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. Ce(1) is bonded to four Si(2,2) and eight equivalent Si(1) atoms to form CeSi12 cuboctahedra that share edges with four equivalent Ce(1)Si12 cuboctahedra, edges with eight equivalent Th(1)Si12 cuboctahedra, faces with four equivalent Th(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Th(1), four equivalent Ce(1), one Si(1), and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. In the third Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. In the fourth Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Th(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_CeThSi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.696
_cell_length_b   7.696
_cell_length_c   7.696
_cell_angle_alpha   148.935
_cell_angle_beta   148.935
_cell_angle_gamma   44.506
_symmetry_Int_Tables_number   1
_cell_volume   120.996
_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  0.250  0.750  0.500  1.0
  Th  Th1  1  0.000  0.000  0.000  1.0
  Si  Si2  1  0.667  0.167  0.500  1.0
  Si  Si3  1  0.584  0.584  0.000  1.0
  Si  Si4  1  0.833  0.333  0.500  1.0
  Si  Si5  1  0.416  0.416  0.000  1.0
[/CIF]
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