The structure described by Th2Ce2O7 crystallizes in the tetragonal P-4m2 space group. Th(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Ce(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ce(1) atoms to form OCe4 tetrahedra that share corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra, corners with eight equivalent O(2)Ce2Th2 tetrahedra, and edges with two equivalent O(3)Ce2Th2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with two equivalent O(5)Th4 tetrahedra, corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra, corners with four equivalent O(4)Th4 tetrahedra,  an edgeedge with one O(5)Th4 tetrahedra, and edges with four equivalent O(3)Ce2Th2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(4)Th4 tetrahedra, corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(5)Th4 tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Th4 tetrahedra, and edges with four equivalent O(2)Ce2Th2 tetrahedra. In the fourth O site, O(4) is bonded to four equivalent Th(1) atoms to form OTh4 tetrahedra that share corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(4)Th4 tetrahedra, corners with eight equivalent O(2)Ce2Th2 tetrahedra, edges with two equivalent O(3)Ce2Th2 tetrahedra, and edges with four equivalent O(5)Th4 tetrahedra. In the fifth O site, O(5) is bonded to four equivalent Th(1) atoms to form OTh4 tetrahedra that share corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with four equivalent O(5)Th4 tetrahedra, corners with eight equivalent O(3)Ce2Th2 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(4)Th4 tetrahedra. is represented by the CIF file [CIF]
data_Ce2Th2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.951
_cell_length_b   3.951
_cell_length_c   11.195
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   174.747
_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  0.500  0.000  0.867  1.0
  Ce  Ce1  1  0.000  0.500  0.133  1.0
  Th  Th2  1  0.500  0.000  0.374  1.0
  Th  Th3  1  0.000  0.500  0.626  1.0
  O  O4  1  0.500  0.500  0.000  1.0
  O  O5  1  0.000  0.000  0.239  1.0
  O  O6  1  0.500  0.500  0.256  1.0
  O  O7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.000  0.000  0.500  1.0
  O  O9  1  0.500  0.500  0.744  1.0
  O  O10  1  0.000  0.000  0.761  1.0
[/CIF]
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The structure described by Th2Ce2O7 crystallizes in the tetragonal P-4m2 space group. Th(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Ce(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ce(1) atoms to form OCe4 tetrahedra that share corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra, corners with eight equivalent O(2)Ce2Th2 tetrahedra, and edges with two equivalent O(3)Ce2Th2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with two equivalent O(5)Th4 tetrahedra, corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with four equivalent O(1)Ce4 tetrahedra, corners with four equivalent O(4)Th4 tetrahedra,  an edgeedge with one O(5)Th4 tetrahedra, and edges with four equivalent O(3)Ce2Th2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(4)Th4 tetrahedra, corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(5)Th4 tetrahedra,  an edgeedge with one O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Th4 tetrahedra, and edges with four equivalent O(2)Ce2Th2 tetrahedra. In the fourth O site, O(4) is bonded to four equivalent Th(1) atoms to form OTh4 tetrahedra that share corners with four equivalent O(3)Ce2Th2 tetrahedra, corners with four equivalent O(4)Th4 tetrahedra, corners with eight equivalent O(2)Ce2Th2 tetrahedra, edges with two equivalent O(3)Ce2Th2 tetrahedra, and edges with four equivalent O(5)Th4 tetrahedra. In the fifth O site, O(5) is bonded to four equivalent Th(1) atoms to form OTh4 tetrahedra that share corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with four equivalent O(5)Th4 tetrahedra, corners with eight equivalent O(3)Ce2Th2 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(4)Th4 tetrahedra. is represented by the CIF file [CIF]
data_Ce2Th2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.951
_cell_length_b   3.951
_cell_length_c   11.195
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   174.747
_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  0.500  0.000  0.867  1.0
  Ce  Ce1  1  0.000  0.500  0.133  1.0
  Th  Th2  1  0.500  0.000  0.374  1.0
  Th  Th3  1  0.000  0.500  0.626  1.0
  O  O4  1  0.500  0.500  0.000  1.0
  O  O5  1  0.000  0.000  0.239  1.0
  O  O6  1  0.500  0.500  0.256  1.0
  O  O7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.000  0.000  0.500  1.0
  O  O9  1  0.500  0.500  0.744  1.0
  O  O10  1  0.000  0.000  0.761  1.0
[/CIF]
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