The crystal structure described by K3FeO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a linear geometry to two equivalent O(1) atoms. In the second K site, K(2) is bonded to four equivalent O(1) atoms to form a mixture of edge and corner-sharing KO4 tetrahedra. Fe(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one K(1), four equivalent K(2), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OK5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-70°. is represented by the CIF card [CIF]
data_K3FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.192
_cell_length_b   6.192
_cell_length_c   14.647
_cell_angle_alpha   90.008
_cell_angle_beta   89.998
_cell_angle_gamma   89.916
_symmetry_Int_Tables_number   1
_cell_volume   561.634
_cell_formula_units_Z   4
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  0.969  0.969  0.500  1.0
  K  K1  1  0.531  0.469  0.750  1.0
  K  K2  1  0.469  0.531  0.250  1.0
  K  K3  1  0.031  0.031  0.000  1.0
  K  K4  1  0.511  0.015  0.125  1.0
  K  K5  1  0.515  0.989  0.875  1.0
  K  K6  1  0.011  0.485  0.625  1.0
  K  K7  1  0.489  0.985  0.625  1.0
  K  K8  1  0.015  0.511  0.875  1.0
  K  K9  1  0.985  0.489  0.375  1.0
  K  K10  1  0.485  0.011  0.375  1.0
  K  K11  1  0.989  0.515  0.125  1.0
  Fe  Fe12  1  0.004  0.996  0.750  1.0
  Fe  Fe13  1  0.996  0.004  0.250  1.0
  Fe  Fe14  1  0.496  0.496  0.500  1.0
  Fe  Fe15  1  0.504  0.504  1.000  1.0
  O  O16  1  0.787  0.797  0.257  1.0
  O  O17  1  0.213  0.203  0.757  1.0
  O  O18  1  0.797  0.787  0.743  1.0
  O  O19  1  0.297  0.713  0.007  1.0
  O  O20  1  0.287  0.703  0.493  1.0
  O  O21  1  0.203  0.213  0.243  1.0
  O  O22  1  0.703  0.287  0.507  1.0
  O  O23  1  0.713  0.297  0.993  1.0
[/CIF]
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The crystal structure described by K3FeO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a linear geometry to two equivalent O(1) atoms. In the second K site, K(2) is bonded to four equivalent O(1) atoms to form a mixture of edge and corner-sharing KO4 tetrahedra. Fe(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one K(1), four equivalent K(2), and one Fe(1) atom to form a mixture of distorted edge and corner-sharing OK5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-70°. is represented by the CIF card [CIF]
data_K3FeO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.192
_cell_length_b   6.192
_cell_length_c   14.647
_cell_angle_alpha   90.008
_cell_angle_beta   89.998
_cell_angle_gamma   89.916
_symmetry_Int_Tables_number   1
_cell_volume   561.634
_cell_formula_units_Z   4
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  0.969  0.969  0.500  1.0
  K  K1  1  0.531  0.469  0.750  1.0
  K  K2  1  0.469  0.531  0.250  1.0
  K  K3  1  0.031  0.031  0.000  1.0
  K  K4  1  0.511  0.015  0.125  1.0
  K  K5  1  0.515  0.989  0.875  1.0
  K  K6  1  0.011  0.485  0.625  1.0
  K  K7  1  0.489  0.985  0.625  1.0
  K  K8  1  0.015  0.511  0.875  1.0
  K  K9  1  0.985  0.489  0.375  1.0
  K  K10  1  0.485  0.011  0.375  1.0
  K  K11  1  0.989  0.515  0.125  1.0
  Fe  Fe12  1  0.004  0.996  0.750  1.0
  Fe  Fe13  1  0.996  0.004  0.250  1.0
  Fe  Fe14  1  0.496  0.496  0.500  1.0
  Fe  Fe15  1  0.504  0.504  1.000  1.0
  O  O16  1  0.787  0.797  0.257  1.0
  O  O17  1  0.213  0.203  0.757  1.0
  O  O18  1  0.797  0.787  0.743  1.0
  O  O19  1  0.297  0.713  0.007  1.0
  O  O20  1  0.287  0.703  0.493  1.0
  O  O21  1  0.203  0.213  0.243  1.0
  O  O22  1  0.703  0.287  0.507  1.0
  O  O23  1  0.713  0.297  0.993  1.0
[/CIF]
.