The compound described by Ce4La3O12 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form distorted CeO7 hexagonal pyramids that share  a cornercorner with one La(1)O6 octahedra and edges with two equivalent Ce(1)O7 hexagonal pyramids. The corner-sharing octahedral tilt angles are 58°. In the second Ce site, Ce(2) is bonded in a body-centered cubic geometry to one O(1), one O(3), three equivalent O(4), and three equivalent O(6) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded to two equivalent O(5) and four equivalent O(2) atoms to form LaO6 octahedra that share corners with two equivalent Ce(1)O7 hexagonal pyramids and edges with two equivalent La(1)O6 octahedra. In the second La site, La(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2), two equivalent Ce(1), and one La(2) atom to form distorted OLaCe3 tetrahedra that share  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)La4 tetrahedra, corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with four equivalent O(5)La3Ce tetrahedra, corners with five equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the second O site, O(2) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form distorted OLa4 tetrahedra that share corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with four equivalent O(5)La3Ce tetrahedra, corners with four equivalent O(2)La4 tetrahedra, edges with two equivalent O(5)La3Ce tetrahedra, and edges with two equivalent O(2)La4 tetrahedra. In the third O site, O(3) is bonded to one Ce(2), two equivalent Ce(1), and one La(2) atom to form OLaCe3 tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra, corners with two equivalent O(2)La4 tetrahedra, corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with five equivalent O(6)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(5)La3Ce tetrahedra, and edges with two equivalent O(1)LaCe3 tetrahedra. In the fourth O site, O(4) is bonded to one Ce(1) and three equivalent Ce(2) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)La3Ce tetrahedra,  a cornercorner with one O(3)LaCe3 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(1)LaCe3 tetrahedra, corners with six equivalent O(6)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the fifth O site, O(5) is bonded to one Ce(1), one La(1), and two equivalent La(2) atoms to form OLa3Ce tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with three equivalent O(5)La3Ce tetrahedra, corners with four equivalent O(2)La4 tetrahedra, corners with four equivalent O(1)LaCe3 tetrahedra, edges with two equivalent O(2)La4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the sixth O site, O(6) is bonded to one Ce(1) and three equivalent Ce(2) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)La3Ce tetrahedra,  a cornercorner with one O(1)LaCe3 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with five equivalent O(3)LaCe3 tetrahedra, corners with six equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(1)LaCe3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3Ce4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.429
_cell_length_b   14.429
_cell_length_c   5.631
_cell_angle_alpha   79.195
_cell_angle_beta   79.195
_cell_angle_gamma   15.350
_symmetry_Int_Tables_number   1
_cell_volume   304.756
_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
  La  La0  1  0.000  0.000  0.000  1.0
  La  La1  1  0.427  0.427  0.526  1.0
  La  La2  1  0.573  0.573  0.474  1.0
  Ce  Ce3  1  0.152  0.152  0.836  1.0
  Ce  Ce4  1  0.286  0.286  0.714  1.0
  Ce  Ce5  1  0.848  0.848  0.164  1.0
  Ce  Ce6  1  0.714  0.714  0.286  1.0
  O  O7  1  0.636  0.636  0.107  1.0
  O  O8  1  0.513  0.513  0.238  1.0
  O  O9  1  0.350  0.350  0.397  1.0
  O  O10  1  0.216  0.216  0.528  1.0
  O  O11  1  0.650  0.650  0.603  1.0
  O  O12  1  0.075  0.075  0.708  1.0
  O  O13  1  0.925  0.925  0.292  1.0
  O  O14  1  0.487  0.487  0.762  1.0
  O  O15  1  0.784  0.784  0.471  1.0
  O  O16  1  0.214  0.214  0.031  1.0
  O  O17  1  0.786  0.786  0.969  1.0
  O  O18  1  0.364  0.364  0.893  1.0
[/CIF]
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The compound described by Ce4La3O12 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form distorted CeO7 hexagonal pyramids that share  a cornercorner with one La(1)O6 octahedra and edges with two equivalent Ce(1)O7 hexagonal pyramids. The corner-sharing octahedral tilt angles are 58°. In the second Ce site, Ce(2) is bonded in a body-centered cubic geometry to one O(1), one O(3), three equivalent O(4), and three equivalent O(6) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded to two equivalent O(5) and four equivalent O(2) atoms to form LaO6 octahedra that share corners with two equivalent Ce(1)O7 hexagonal pyramids and edges with two equivalent La(1)O6 octahedra. In the second La site, La(2) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2), two equivalent Ce(1), and one La(2) atom to form distorted OLaCe3 tetrahedra that share  a cornercorner with one O(6)Ce4 tetrahedra, corners with two equivalent O(2)La4 tetrahedra, corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with four equivalent O(5)La3Ce tetrahedra, corners with five equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the second O site, O(2) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form distorted OLa4 tetrahedra that share corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with four equivalent O(5)La3Ce tetrahedra, corners with four equivalent O(2)La4 tetrahedra, edges with two equivalent O(5)La3Ce tetrahedra, and edges with two equivalent O(2)La4 tetrahedra. In the third O site, O(3) is bonded to one Ce(2), two equivalent Ce(1), and one La(2) atom to form OLaCe3 tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra, corners with two equivalent O(2)La4 tetrahedra, corners with two equivalent O(1)LaCe3 tetrahedra, corners with two equivalent O(3)LaCe3 tetrahedra, corners with five equivalent O(6)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(5)La3Ce tetrahedra, and edges with two equivalent O(1)LaCe3 tetrahedra. In the fourth O site, O(4) is bonded to one Ce(1) and three equivalent Ce(2) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)La3Ce tetrahedra,  a cornercorner with one O(3)LaCe3 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(1)LaCe3 tetrahedra, corners with six equivalent O(6)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the fifth O site, O(5) is bonded to one Ce(1), one La(1), and two equivalent La(2) atoms to form OLa3Ce tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra,  a cornercorner with one O(6)Ce4 tetrahedra, corners with three equivalent O(5)La3Ce tetrahedra, corners with four equivalent O(2)La4 tetrahedra, corners with four equivalent O(1)LaCe3 tetrahedra, edges with two equivalent O(2)La4 tetrahedra, and edges with two equivalent O(3)LaCe3 tetrahedra. In the sixth O site, O(6) is bonded to one Ce(1) and three equivalent Ce(2) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)La3Ce tetrahedra,  a cornercorner with one O(1)LaCe3 tetrahedra, corners with two equivalent O(6)Ce4 tetrahedra, corners with five equivalent O(3)LaCe3 tetrahedra, corners with six equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, edges with two equivalent O(6)Ce4 tetrahedra, and edges with two equivalent O(1)LaCe3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3Ce4O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.429
_cell_length_b   14.429
_cell_length_c   5.631
_cell_angle_alpha   79.195
_cell_angle_beta   79.195
_cell_angle_gamma   15.350
_symmetry_Int_Tables_number   1
_cell_volume   304.756
_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
  La  La0  1  0.000  0.000  0.000  1.0
  La  La1  1  0.427  0.427  0.526  1.0
  La  La2  1  0.573  0.573  0.474  1.0
  Ce  Ce3  1  0.152  0.152  0.836  1.0
  Ce  Ce4  1  0.286  0.286  0.714  1.0
  Ce  Ce5  1  0.848  0.848  0.164  1.0
  Ce  Ce6  1  0.714  0.714  0.286  1.0
  O  O7  1  0.636  0.636  0.107  1.0
  O  O8  1  0.513  0.513  0.238  1.0
  O  O9  1  0.350  0.350  0.397  1.0
  O  O10  1  0.216  0.216  0.528  1.0
  O  O11  1  0.650  0.650  0.603  1.0
  O  O12  1  0.075  0.075  0.708  1.0
  O  O13  1  0.925  0.925  0.292  1.0
  O  O14  1  0.487  0.487  0.762  1.0
  O  O15  1  0.784  0.784  0.471  1.0
  O  O16  1  0.214  0.214  0.031  1.0
  O  O17  1  0.786  0.786  0.969  1.0
  O  O18  1  0.364  0.364  0.893  1.0
[/CIF]
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