The compound described by SmCe4O9 crystallizes in the orthorhombic Imm2 space group. Sm(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a body-centered cubic geometry to one O(2), one O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Ce site, Ce(2) is bonded to one O(1), one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing CeO7 hexagonal pyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2) and three equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)Ce2Sm2 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(3)Ce3Sm tetrahedra, corners with six equivalent O(1)Ce4 tetrahedra,  a cornercorner with one O(2)Ce3Sm trigonal pyramid, edges with four equivalent O(4)Ce4 tetrahedra, and edges with two equivalent O(2)Ce3Sm trigonal pyramids. In the second O site, O(2) is bonded to one Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form distorted OCe3Sm trigonal pyramids that share  a cornercorner with one O(1)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with four equivalent O(5)Ce2Sm2 tetrahedra, corners with five equivalent O(4)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(3)Ce3Sm tetrahedra, and edges with two equivalent O(1)Ce4 tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form OCe3Sm tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with five equivalent O(1)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(5)Ce2Sm2 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, and edges with two equivalent O(2)Ce3Sm trigonal pyramids. In the fourth O site, O(4) is bonded to one Ce(2) and three equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)Ce2Sm2 tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with six equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(3)Ce3Sm tetrahedra, and edges with four equivalent O(1)Ce4 tetrahedra. In the fifth O site, O(5) is bonded to two equivalent Sm(1) and two equivalent Ce(2) atoms to form OCe2Sm2 tetrahedra that share corners with two equivalent O(5)Ce2Sm2 tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with eight equivalent O(2)Ce3Sm trigonal pyramids, and edges with four equivalent O(3)Ce3Sm tetrahedra. is represented by the CIF file [CIF]
data_Ce4SmO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.449
_cell_length_b   10.449
_cell_length_c   10.449
_cell_angle_alpha   158.932
_cell_angle_beta   149.175
_cell_angle_gamma   37.638
_symmetry_Int_Tables_number   1
_cell_volume   209.839
_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  0.693  0.700  0.993  1.0
  Ce  Ce1  1  0.881  0.893  0.988  1.0
  Ce  Ce2  1  0.095  0.107  0.988  1.0
  Ce  Ce3  1  0.293  0.300  0.993  1.0
  Sm  Sm4  1  0.548  0.500  0.048  1.0
  O  O5  1  0.044  0.804  0.240  1.0
  O  O6  1  0.158  0.416  0.742  1.0
  O  O7  1  0.326  0.584  0.742  1.0
  O  O8  1  0.437  0.196  0.240  1.0
  O  O9  1  0.644  0.394  0.250  1.0
  O  O10  1  0.539  0.797  0.741  1.0
  O  O11  1  0.944  0.203  0.741  1.0
  O  O12  1  0.856  0.606  0.250  1.0
  O  O13  1  0.773  0.000  0.773  1.0
[/CIF]
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The compound described by SmCe4O9 crystallizes in the orthorhombic Imm2 space group. Sm(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a body-centered cubic geometry to one O(2), one O(3), three equivalent O(1), and three equivalent O(4) atoms. In the second Ce site, Ce(2) is bonded to one O(1), one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing CeO7 hexagonal pyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Ce(2) and three equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)Ce2Sm2 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(3)Ce3Sm tetrahedra, corners with six equivalent O(1)Ce4 tetrahedra,  a cornercorner with one O(2)Ce3Sm trigonal pyramid, edges with four equivalent O(4)Ce4 tetrahedra, and edges with two equivalent O(2)Ce3Sm trigonal pyramids. In the second O site, O(2) is bonded to one Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form distorted OCe3Sm trigonal pyramids that share  a cornercorner with one O(1)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with four equivalent O(5)Ce2Sm2 tetrahedra, corners with five equivalent O(4)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(3)Ce3Sm tetrahedra, and edges with two equivalent O(1)Ce4 tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form OCe3Sm tetrahedra that share  a cornercorner with one O(4)Ce4 tetrahedra, corners with three equivalent O(3)Ce3Sm tetrahedra, corners with five equivalent O(1)Ce4 tetrahedra, corners with three equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(5)Ce2Sm2 tetrahedra, edges with two equivalent O(4)Ce4 tetrahedra, and edges with two equivalent O(2)Ce3Sm trigonal pyramids. In the fourth O site, O(4) is bonded to one Ce(2) and three equivalent Ce(1) atoms to form OCe4 tetrahedra that share  a cornercorner with one O(5)Ce2Sm2 tetrahedra,  a cornercorner with one O(3)Ce3Sm tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with six equivalent O(4)Ce4 tetrahedra, corners with five equivalent O(2)Ce3Sm trigonal pyramids, edges with two equivalent O(3)Ce3Sm tetrahedra, and edges with four equivalent O(1)Ce4 tetrahedra. In the fifth O site, O(5) is bonded to two equivalent Sm(1) and two equivalent Ce(2) atoms to form OCe2Sm2 tetrahedra that share corners with two equivalent O(5)Ce2Sm2 tetrahedra, corners with two equivalent O(1)Ce4 tetrahedra, corners with two equivalent O(4)Ce4 tetrahedra, corners with eight equivalent O(2)Ce3Sm trigonal pyramids, and edges with four equivalent O(3)Ce3Sm tetrahedra. is represented by the CIF file [CIF]
data_Ce4SmO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.449
_cell_length_b   10.449
_cell_length_c   10.449
_cell_angle_alpha   158.932
_cell_angle_beta   149.175
_cell_angle_gamma   37.638
_symmetry_Int_Tables_number   1
_cell_volume   209.839
_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  0.693  0.700  0.993  1.0
  Ce  Ce1  1  0.881  0.893  0.988  1.0
  Ce  Ce2  1  0.095  0.107  0.988  1.0
  Ce  Ce3  1  0.293  0.300  0.993  1.0
  Sm  Sm4  1  0.548  0.500  0.048  1.0
  O  O5  1  0.044  0.804  0.240  1.0
  O  O6  1  0.158  0.416  0.742  1.0
  O  O7  1  0.326  0.584  0.742  1.0
  O  O8  1  0.437  0.196  0.240  1.0
  O  O9  1  0.644  0.394  0.250  1.0
  O  O10  1  0.539  0.797  0.741  1.0
  O  O11  1  0.944  0.203  0.741  1.0
  O  O12  1  0.856  0.606  0.250  1.0
  O  O13  1  0.773  0.000  0.773  1.0
[/CIF]
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