The material structure described by CsFe(SeO4)2 crystallizes in the trigonal P321 space group. Cs(1) is bonded to six equivalent O(2) atoms to form distorted CsO6 cuboctahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with six equivalent Cs(1)O6 cuboctahedra. Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 pentagonal pyramids that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(2) and three equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Cs(1)O6 cuboctahedra and corners with three equivalent Fe(1)O6 pentagonal pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Cs(1) and one Se(1) atom. is represented by the CIF file [CIF]
data_CsFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.234
_cell_length_b   5.234
_cell_length_c   9.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   217.979
_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
  Cs  Cs0  1  0.000  0.000  0.500  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  Se  Se2  1  0.667  0.333  0.801  1.0
  Se  Se3  1  0.333  0.667  0.199  1.0
  O  O4  1  0.926  0.259  0.860  1.0
  O  O5  1  0.332  0.074  0.860  1.0
  O  O6  1  0.668  0.741  0.140  1.0
  O  O7  1  0.741  0.668  0.860  1.0
  O  O8  1  0.259  0.926  0.140  1.0
  O  O9  1  0.074  0.332  0.140  1.0
  O  O10  1  0.667  0.333  0.622  1.0
  O  O11  1  0.333  0.667  0.378  1.0
[/CIF]
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The material structure described by CsFe(SeO4)2 crystallizes in the trigonal P321 space group. Cs(1) is bonded to six equivalent O(2) atoms to form distorted CsO6 cuboctahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with six equivalent Cs(1)O6 cuboctahedra. Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 pentagonal pyramids that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(2) and three equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Cs(1)O6 cuboctahedra and corners with three equivalent Fe(1)O6 pentagonal pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Cs(1) and one Se(1) atom. is represented by the CIF file [CIF]
data_CsFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.234
_cell_length_b   5.234
_cell_length_c   9.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   217.979
_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
  Cs  Cs0  1  0.000  0.000  0.500  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  Se  Se2  1  0.667  0.333  0.801  1.0
  Se  Se3  1  0.333  0.667  0.199  1.0
  O  O4  1  0.926  0.259  0.860  1.0
  O  O5  1  0.332  0.074  0.860  1.0
  O  O6  1  0.668  0.741  0.140  1.0
  O  O7  1  0.741  0.668  0.860  1.0
  O  O8  1  0.259  0.926  0.140  1.0
  O  O9  1  0.074  0.332  0.140  1.0
  O  O10  1  0.667  0.333  0.622  1.0
  O  O11  1  0.333  0.667  0.378  1.0
[/CIF]
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