The crystal structure described by Th3Ce3Si4 crystallizes in the monoclinic Pm space group. There are three inequivalent Th sites. In the first Th site, Th(1) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the second Th site, Th(2) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(4) atoms. In the third Th site, Th(3) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a distorted square co-planar geometry to one Si(1), one Si(2), one Si(3), and one Si(4) atom. In the second Ce site, Ce(2) is bonded in a distorted rectangular see-saw-like geometry to one Si(1), one Si(2), one Si(3), and one Si(4) atom. In the third Ce site, Ce(3) is bonded in a distorted hexagonal planar geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. 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), two equivalent Th(2), two equivalent Th(3), one Ce(1), one Ce(2), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Th(2), two equivalent Th(3), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(1) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Th(1), two equivalent Th(3), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(4) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Th(1), two equivalent Th(2), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce3Th3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.813
_cell_length_b   7.852
_cell_length_c   4.193
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   89.461
_symmetry_Int_Tables_number   1
_cell_volume   257.185
_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  0.501  1.000  0.000  1.0
  Ce  Ce1  1  0.998  0.502  0.000  1.0
  Ce  Ce2  1  0.682  0.677  0.500  1.0
  Th  Th3  1  0.318  0.321  0.500  1.0
  Th  Th4  1  0.181  0.820  0.500  1.0
  Th  Th5  1  0.822  0.181  0.500  1.0
  Si  Si6  1  0.114  0.112  0.000  1.0
  Si  Si7  1  0.889  0.892  0.000  1.0
  Si  Si8  1  0.608  0.385  0.000  1.0
  Si  Si9  1  0.389  0.611  0.000  1.0
[/CIF]
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The crystal structure described by Th3Ce3Si4 crystallizes in the monoclinic Pm space group. There are three inequivalent Th sites. In the first Th site, Th(1) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(3), and two equivalent Si(4) atoms. In the second Th site, Th(2) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(4) atoms. In the third Th site, Th(3) is bonded in a 6-coordinate geometry to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a distorted square co-planar geometry to one Si(1), one Si(2), one Si(3), and one Si(4) atom. In the second Ce site, Ce(2) is bonded in a distorted rectangular see-saw-like geometry to one Si(1), one Si(2), one Si(3), and one Si(4) atom. In the third Ce site, Ce(3) is bonded in a distorted hexagonal planar geometry to two equivalent Si(2), two equivalent Si(3), and two equivalent Si(4) atoms. 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), two equivalent Th(2), two equivalent Th(3), one Ce(1), one Ce(2), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Th(2), two equivalent Th(3), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(1) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Th(1), two equivalent Th(3), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(4) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Th(1), two equivalent Th(2), one Ce(1), one Ce(2), two equivalent Ce(3), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce3Th3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.813
_cell_length_b   7.852
_cell_length_c   4.193
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   89.461
_symmetry_Int_Tables_number   1
_cell_volume   257.185
_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  0.501  1.000  0.000  1.0
  Ce  Ce1  1  0.998  0.502  0.000  1.0
  Ce  Ce2  1  0.682  0.677  0.500  1.0
  Th  Th3  1  0.318  0.321  0.500  1.0
  Th  Th4  1  0.181  0.820  0.500  1.0
  Th  Th5  1  0.822  0.181  0.500  1.0
  Si  Si6  1  0.114  0.112  0.000  1.0
  Si  Si7  1  0.889  0.892  0.000  1.0
  Si  Si8  1  0.608  0.385  0.000  1.0
  Si  Si9  1  0.389  0.611  0.000  1.0
[/CIF]
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