The structure described by SmCeO2 is Caswellsilverite-like structured and crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form SmO6 octahedra that share corners with two equivalent Ce(2)O6 octahedra, corners with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, edges with four equivalent Ce(1)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Sm site, Sm(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form SmO6 octahedra that share corners with two equivalent Ce(1)O6 octahedra, corners with four equivalent Sm(2)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Ce(1)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CeO6 octahedra that share corners with two equivalent Sm(2)O6 octahedra, corners with four equivalent Ce(1)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Ce site, Ce(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form CeO6 octahedra that share corners with two equivalent Sm(1)O6 octahedra, corners with four equivalent Ce(2)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, and edges with four equivalent Ce(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Sm(1), two equivalent Sm(2), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(2) is bonded to one Sm(1), two equivalent Sm(2), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the third O site, O(3) is bonded to one Sm(2), two equivalent Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth O site, O(4) is bonded to one Sm(2), two equivalent Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. is represented by the CIF card [CIF]
data_CeSmO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.096
_cell_length_b   6.096
_cell_length_c   6.096
_cell_angle_alpha   131.799
_cell_angle_beta   131.799
_cell_angle_gamma   70.547
_symmetry_Int_Tables_number   1
_cell_volume   123.366
_cell_formula_units_Z   2
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
  Ce  Ce1  1  0.500  0.500  0.000  1.0
  Sm  Sm2  1  0.995  0.995  0.000  1.0
  Sm  Sm3  1  0.745  0.245  0.500  1.0
  O  O4  1  0.745  0.745  0.000  1.0
  O  O5  1  0.242  0.242  0.000  1.0
  O  O6  1  0.495  0.995  0.500  1.0
  O  O7  1  0.005  0.505  0.500  1.0
[/CIF]
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The structure described by SmCeO2 is Caswellsilverite-like structured and crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form SmO6 octahedra that share corners with two equivalent Ce(2)O6 octahedra, corners with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, edges with four equivalent Ce(1)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Sm site, Sm(2) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form SmO6 octahedra that share corners with two equivalent Ce(1)O6 octahedra, corners with four equivalent Sm(2)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Ce(1)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CeO6 octahedra that share corners with two equivalent Sm(2)O6 octahedra, corners with four equivalent Ce(1)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, and edges with four equivalent Ce(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Ce site, Ce(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form CeO6 octahedra that share corners with two equivalent Sm(1)O6 octahedra, corners with four equivalent Ce(2)O6 octahedra, edges with four equivalent Sm(1)O6 octahedra, edges with four equivalent Sm(2)O6 octahedra, and edges with four equivalent Ce(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Sm(1), two equivalent Sm(2), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second O site, O(2) is bonded to one Sm(1), two equivalent Sm(2), one Ce(2), and two equivalent Ce(1) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the third O site, O(3) is bonded to one Sm(2), two equivalent Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth O site, O(4) is bonded to one Sm(2), two equivalent Sm(1), one Ce(1), and two equivalent Ce(2) atoms to form a mixture of edge and corner-sharing OCe3Sm3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. is represented by the CIF card [CIF]
data_CeSmO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.096
_cell_length_b   6.096
_cell_length_c   6.096
_cell_angle_alpha   131.799
_cell_angle_beta   131.799
_cell_angle_gamma   70.547
_symmetry_Int_Tables_number   1
_cell_volume   123.366
_cell_formula_units_Z   2
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
  Ce  Ce1  1  0.500  0.500  0.000  1.0
  Sm  Sm2  1  0.995  0.995  0.000  1.0
  Sm  Sm3  1  0.745  0.245  0.500  1.0
  O  O4  1  0.745  0.745  0.000  1.0
  O  O5  1  0.242  0.242  0.000  1.0
  O  O6  1  0.495  0.995  0.500  1.0
  O  O7  1  0.005  0.505  0.500  1.0
[/CIF]
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