The structure described by FeCo3O8 crystallizes in the trigonal R3m space group. Fe(1) is bonded to one O(4) and three equivalent O(3) atoms to form FeO4 tetrahedra that share corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. Co(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra and edges with four equivalent Co(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Co(1) atoms. In the second O site, O(2) is bonded in a water-like geometry to two equivalent Co(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal pyramidal geometry to one Fe(1) and three equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_FeCo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   5.725
_cell_angle_alpha   59.527
_cell_angle_beta   59.527
_cell_angle_gamma   59.527
_symmetry_Int_Tables_number   1
_cell_volume   131.276
_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
  Fe  Fe0  1  0.878  0.878  0.878  1.0
  Co  Co1  1  0.009  0.496  0.496  1.0
  Co  Co2  1  0.496  0.496  0.009  1.0
  Co  Co3  1  0.496  0.009  0.496  1.0
  O  O4  1  0.263  0.263  0.263  1.0
  O  O5  1  0.249  0.703  0.249  1.0
  O  O6  1  0.249  0.249  0.703  1.0
  O  O7  1  0.703  0.249  0.249  1.0
  O  O8  1  0.286  0.753  0.753  1.0
  O  O9  1  0.753  0.753  0.286  1.0
  O  O10  1  0.753  0.286  0.753  1.0
  O  O11  1  0.740  0.740  0.740  1.0
[/CIF]
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The structure described by FeCo3O8 crystallizes in the trigonal R3m space group. Fe(1) is bonded to one O(4) and three equivalent O(3) atoms to form FeO4 tetrahedra that share corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. Co(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra and edges with four equivalent Co(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Co(1) atoms. In the second O site, O(2) is bonded in a water-like geometry to two equivalent Co(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal pyramidal geometry to one Fe(1) and three equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_FeCo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   5.725
_cell_angle_alpha   59.527
_cell_angle_beta   59.527
_cell_angle_gamma   59.527
_symmetry_Int_Tables_number   1
_cell_volume   131.276
_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
  Fe  Fe0  1  0.878  0.878  0.878  1.0
  Co  Co1  1  0.009  0.496  0.496  1.0
  Co  Co2  1  0.496  0.496  0.009  1.0
  Co  Co3  1  0.496  0.009  0.496  1.0
  O  O4  1  0.263  0.263  0.263  1.0
  O  O5  1  0.249  0.703  0.249  1.0
  O  O6  1  0.249  0.249  0.703  1.0
  O  O7  1  0.703  0.249  0.249  1.0
  O  O8  1  0.286  0.753  0.753  1.0
  O  O9  1  0.753  0.753  0.286  1.0
  O  O10  1  0.753  0.286  0.753  1.0
  O  O11  1  0.740  0.740  0.740  1.0
[/CIF]
.