The crystal structure described by Sm(FeO2)2 crystallizes in the trigonal R-3m space group. Sm(1) is bonded to six equivalent O(2) atoms to form distorted SmO6 octahedra that share corners with six equivalent Fe(1)O5 trigonal bipyramids and edges with six equivalent Sm(1)O6 octahedra. Fe(1) is bonded to one O(2) and four equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent Sm(1)O6 octahedra, corners with six equivalent Fe(1)O5 trigonal bipyramids, and edges with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Fe(1) atoms to form OFe4 trigonal pyramids that share corners with four equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(1)Fe4 trigonal pyramids. In the second O site, O(2) is bonded to three equivalent Sm(1) and one Fe(1) atom to form OSm3Fe tetrahedra that share corners with nine equivalent O(2)Sm3Fe tetrahedra, corners with four equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(2)Sm3Fe tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.607
_cell_length_b   8.497
_cell_length_c   3.611
_cell_angle_alpha   102.273
_cell_angle_beta   59.944
_cell_angle_gamma   102.252
_symmetry_Int_Tables_number   1
_cell_volume   92.864
_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
  Sm  Sm0  1  0.000  1.000  0.000  1.0
  Fe  Fe1  1  0.211  0.634  0.211  1.0
  Fe  Fe2  1  0.789  0.366  0.789  1.0
  O  O3  1  0.127  0.382  0.127  1.0
  O  O4  1  0.290  0.870  0.290  1.0
  O  O5  1  0.710  0.130  0.710  1.0
  O  O6  1  0.873  0.618  0.873  1.0
[/CIF]
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The crystal structure described by Sm(FeO2)2 crystallizes in the trigonal R-3m space group. Sm(1) is bonded to six equivalent O(2) atoms to form distorted SmO6 octahedra that share corners with six equivalent Fe(1)O5 trigonal bipyramids and edges with six equivalent Sm(1)O6 octahedra. Fe(1) is bonded to one O(2) and four equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent Sm(1)O6 octahedra, corners with six equivalent Fe(1)O5 trigonal bipyramids, and edges with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Fe(1) atoms to form OFe4 trigonal pyramids that share corners with four equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(1)Fe4 trigonal pyramids. In the second O site, O(2) is bonded to three equivalent Sm(1) and one Fe(1) atom to form OSm3Fe tetrahedra that share corners with nine equivalent O(2)Sm3Fe tetrahedra, corners with four equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(2)Sm3Fe tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.607
_cell_length_b   8.497
_cell_length_c   3.611
_cell_angle_alpha   102.273
_cell_angle_beta   59.944
_cell_angle_gamma   102.252
_symmetry_Int_Tables_number   1
_cell_volume   92.864
_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
  Sm  Sm0  1  0.000  1.000  0.000  1.0
  Fe  Fe1  1  0.211  0.634  0.211  1.0
  Fe  Fe2  1  0.789  0.366  0.789  1.0
  O  O3  1  0.127  0.382  0.127  1.0
  O  O4  1  0.290  0.870  0.290  1.0
  O  O5  1  0.710  0.130  0.710  1.0
  O  O6  1  0.873  0.618  0.873  1.0
[/CIF]
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