The material described by K3(FeO2)4 crystallizes in the tetragonal P-4m2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to four equivalent O(2) atoms. In the second K site, K(2) is bonded in a 2-coordinate geometry to two equivalent O(2) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(1) atoms to form distorted corner-sharing FeO4 tetrahedra. In the second Fe site, Fe(2) is bonded to four equivalent O(2) atoms to form corner-sharing FeO4 tetrahedra. In the third Fe site, Fe(3) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing FeO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Fe(1) and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(1), one K(2), one Fe(2), and one Fe(3) atom. is represented by the CIF file [CIF]
data_K3(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.216
_cell_length_b   6.216
_cell_length_c   7.976
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   308.240
_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
  K  K0  1  0.000  0.000  0.500  1.0
  K  K1  1  0.500  0.000  0.207  1.0
  K  K2  1  0.000  0.500  0.793  1.0
  Fe  Fe3  1  0.500  0.500  0.500  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Fe  Fe5  1  0.500  0.000  0.743  1.0
  Fe  Fe6  1  0.000  0.500  0.257  1.0
  O  O7  1  0.767  0.500  0.404  1.0
  O  O8  1  0.243  0.000  0.862  1.0
  O  O9  1  0.757  0.000  0.862  1.0
  O  O10  1  0.233  0.500  0.404  1.0
  O  O11  1  0.500  0.233  0.596  1.0
  O  O12  1  0.000  0.757  0.138  1.0
  O  O13  1  0.500  0.767  0.596  1.0
  O  O14  1  0.000  0.243  0.138  1.0
[/CIF]
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The material described by K3(FeO2)4 crystallizes in the tetragonal P-4m2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to four equivalent O(2) atoms. In the second K site, K(2) is bonded in a 2-coordinate geometry to two equivalent O(2) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(1) atoms to form distorted corner-sharing FeO4 tetrahedra. In the second Fe site, Fe(2) is bonded to four equivalent O(2) atoms to form corner-sharing FeO4 tetrahedra. In the third Fe site, Fe(3) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing FeO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Fe(1) and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(1), one K(2), one Fe(2), and one Fe(3) atom. is represented by the CIF file [CIF]
data_K3(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.216
_cell_length_b   6.216
_cell_length_c   7.976
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   308.240
_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
  K  K0  1  0.000  0.000  0.500  1.0
  K  K1  1  0.500  0.000  0.207  1.0
  K  K2  1  0.000  0.500  0.793  1.0
  Fe  Fe3  1  0.500  0.500  0.500  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Fe  Fe5  1  0.500  0.000  0.743  1.0
  Fe  Fe6  1  0.000  0.500  0.257  1.0
  O  O7  1  0.767  0.500  0.404  1.0
  O  O8  1  0.243  0.000  0.862  1.0
  O  O9  1  0.757  0.000  0.862  1.0
  O  O10  1  0.233  0.500  0.404  1.0
  O  O11  1  0.500  0.233  0.596  1.0
  O  O12  1  0.000  0.757  0.138  1.0
  O  O13  1  0.500  0.767  0.596  1.0
  O  O14  1  0.000  0.243  0.138  1.0
[/CIF]
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