The structure described by Sm(FeO2)2 is Aluminum carbonitride-like structured and crystallizes in the trigonal R3m space group. Sm(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form distorted SmO6 octahedra that share corners with three equivalent Fe(1)O5 trigonal bipyramids, corners with three equivalent Fe(2)O5 trigonal bipyramids, and edges with six equivalent Sm(1)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), and three equivalent O(4) 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(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 64°. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), and three equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent Sm(1)O6 octahedra, corners with six equivalent Fe(2)O5 trigonal bipyramids, and edges with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Fe(1) and three equivalent Fe(2) atoms to form OFe4 trigonal pyramids that share  a cornercorner with one O(2)Sm3Fe tetrahedra, corners with three equivalent O(3)Sm3Fe tetrahedra, corners with six equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(4)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 three equivalent O(3)Sm3Fe tetrahedra, corners with six equivalent O(2)Sm3Fe tetrahedra,  a cornercorner with one O(1)Fe4 trigonal pyramid, corners with three equivalent O(4)Fe4 trigonal pyramids, and edges with three equivalent O(3)Sm3Fe tetrahedra. In the third O site, O(3) is bonded to three equivalent Sm(1) and one Fe(2) atom to form OSm3Fe tetrahedra that share corners with three equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(3)Sm3Fe tetrahedra,  a cornercorner with one O(4)Fe4 trigonal pyramid, corners with three equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(2)Sm3Fe tetrahedra. In the fourth O site, O(4) is bonded to one Fe(2) and three equivalent Fe(1) atoms to form OFe4 trigonal pyramids that share  a cornercorner with one O(3)Sm3Fe tetrahedra, corners with three equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(4)Fe4 trigonal pyramids, and edges with three equivalent O(1)Fe4 trigonal pyramids. is represented by the CIF card [CIF]
data_Sm(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.655
_cell_length_b   8.655
_cell_length_c   8.655
_cell_angle_alpha   24.106
_cell_angle_beta   24.106
_cell_angle_gamma   24.106
_symmetry_Int_Tables_number   1
_cell_volume   95.048
_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  1.000  1.000  1.000  1.0
  Fe  Fe1  1  0.211  0.211  0.211  1.0
  Fe  Fe2  1  0.787  0.787  0.787  1.0
  O  O3  1  0.122  0.122  0.122  1.0
  O  O4  1  0.292  0.292  0.292  1.0
  O  O5  1  0.710  0.710  0.710  1.0
  O  O6  1  0.865  0.865  0.865  1.0
[/CIF]
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The structure described by Sm(FeO2)2 is Aluminum carbonitride-like structured and crystallizes in the trigonal R3m space group. Sm(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form distorted SmO6 octahedra that share corners with three equivalent Fe(1)O5 trigonal bipyramids, corners with three equivalent Fe(2)O5 trigonal bipyramids, and edges with six equivalent Sm(1)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), and three equivalent O(4) 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(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 64°. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), and three equivalent O(1) atoms to form FeO5 trigonal bipyramids that share corners with three equivalent Sm(1)O6 octahedra, corners with six equivalent Fe(2)O5 trigonal bipyramids, and edges with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Fe(1) and three equivalent Fe(2) atoms to form OFe4 trigonal pyramids that share  a cornercorner with one O(2)Sm3Fe tetrahedra, corners with three equivalent O(3)Sm3Fe tetrahedra, corners with six equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(4)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 three equivalent O(3)Sm3Fe tetrahedra, corners with six equivalent O(2)Sm3Fe tetrahedra,  a cornercorner with one O(1)Fe4 trigonal pyramid, corners with three equivalent O(4)Fe4 trigonal pyramids, and edges with three equivalent O(3)Sm3Fe tetrahedra. In the third O site, O(3) is bonded to three equivalent Sm(1) and one Fe(2) atom to form OSm3Fe tetrahedra that share corners with three equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(3)Sm3Fe tetrahedra,  a cornercorner with one O(4)Fe4 trigonal pyramid, corners with three equivalent O(1)Fe4 trigonal pyramids, and edges with three equivalent O(2)Sm3Fe tetrahedra. In the fourth O site, O(4) is bonded to one Fe(2) and three equivalent Fe(1) atoms to form OFe4 trigonal pyramids that share  a cornercorner with one O(3)Sm3Fe tetrahedra, corners with three equivalent O(2)Sm3Fe tetrahedra, corners with six equivalent O(4)Fe4 trigonal pyramids, and edges with three equivalent O(1)Fe4 trigonal pyramids. is represented by the CIF card [CIF]
data_Sm(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.655
_cell_length_b   8.655
_cell_length_c   8.655
_cell_angle_alpha   24.106
_cell_angle_beta   24.106
_cell_angle_gamma   24.106
_symmetry_Int_Tables_number   1
_cell_volume   95.048
_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  1.000  1.000  1.000  1.0
  Fe  Fe1  1  0.211  0.211  0.211  1.0
  Fe  Fe2  1  0.787  0.787  0.787  1.0
  O  O3  1  0.122  0.122  0.122  1.0
  O  O4  1  0.292  0.292  0.292  1.0
  O  O5  1  0.710  0.710  0.710  1.0
  O  O6  1  0.865  0.865  0.865  1.0
[/CIF]
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