The compound described by FeCo3O8 is trigonal omega-derived structured and crystallizes in the tetragonal P4_3 space group. Fe(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form FeO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. In the third Co site, Co(3) is bonded to one O(5), one O(7), two equivalent O(3), and two equivalent O(8) atoms to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(3) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(1), and one Co(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(2), and one Co(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(1) atoms. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(2), and one Co(3) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Co(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.993
_cell_length_b   8.005
_cell_length_c   8.007
_cell_angle_alpha   90.037
_cell_angle_beta   90.044
_cell_angle_gamma   89.916
_symmetry_Int_Tables_number   1
_cell_volume   512.273
_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
  Fe  Fe0  1  0.125  0.875  0.375  1.0
  Fe  Fe1  1  0.375  0.125  0.875  1.0
  Fe  Fe2  1  0.625  0.625  0.625  1.0
  Fe  Fe3  1  0.875  0.375  0.125  1.0
  Co  Co4  1  0.126  0.125  0.625  1.0
  Co  Co5  1  0.125  0.375  0.876  1.0
  Co  Co6  1  0.124  0.625  0.126  1.0
  Co  Co7  1  0.376  0.375  0.625  1.0
  Co  Co8  1  0.375  0.626  0.375  1.0
  Co  Co9  1  0.374  0.876  0.125  1.0
  Co  Co10  1  0.626  0.375  0.375  1.0
  Co  Co11  1  0.625  0.125  0.124  1.0
  Co  Co12  1  0.624  0.875  0.874  1.0
  Co  Co13  1  0.876  0.125  0.375  1.0
  Co  Co14  1  0.875  0.874  0.625  1.0
  Co  Co15  1  0.874  0.624  0.875  1.0
  O  O16  1  0.112  0.110  0.389  1.0
  O  O17  1  0.112  0.888  0.610  1.0
  O  O18  1  0.107  0.607  0.893  1.0
  O  O19  1  0.140  0.139  0.861  1.0
  O  O20  1  0.110  0.389  0.112  1.0
  O  O21  1  0.143  0.357  0.643  1.0
  O  O22  1  0.139  0.640  0.362  1.0
  O  O23  1  0.137  0.861  0.141  1.0
  O  O24  1  0.362  0.139  0.640  1.0
  O  O25  1  0.362  0.360  0.861  1.0
  O  O26  1  0.357  0.643  0.143  1.0
  O  O27  1  0.390  0.611  0.611  1.0
  O  O28  1  0.360  0.862  0.361  1.0
  O  O29  1  0.393  0.393  0.393  1.0
  O  O30  1  0.389  0.112  0.110  1.0
  O  O31  1  0.387  0.891  0.889  1.0
  O  O32  1  0.612  0.390  0.611  1.0
  O  O33  1  0.612  0.611  0.390  1.0
  O  O34  1  0.607  0.893  0.107  1.0
  O  O35  1  0.640  0.361  0.139  1.0
  O  O36  1  0.610  0.111  0.888  1.0
  O  O37  1  0.643  0.143  0.357  1.0
  O  O38  1  0.639  0.860  0.638  1.0
  O  O39  1  0.637  0.639  0.859  1.0
  O  O40  1  0.862  0.361  0.360  1.0
  O  O41  1  0.862  0.140  0.138  1.0
  O  O42  1  0.857  0.857  0.857  1.0
  O  O43  1  0.890  0.889  0.389  1.0
  O  O44  1  0.860  0.638  0.639  1.0
  O  O45  1  0.893  0.107  0.607  1.0
  O  O46  1  0.889  0.388  0.890  1.0
  O  O47  1  0.887  0.610  0.111  1.0
[/CIF]
.
The compound described by FeCo3O8 is trigonal omega-derived structured and crystallizes in the tetragonal P4_3 space group. Fe(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form FeO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. In the third Co site, Co(3) is bonded to one O(5), one O(7), two equivalent O(3), and two equivalent O(8) atoms to form CoO6 octahedra that share edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(3) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(1), and one Co(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(2), and one Co(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(1) atoms. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(1), one Co(2), and one Co(3) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Co(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_FeCo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.993
_cell_length_b   8.005
_cell_length_c   8.007
_cell_angle_alpha   90.037
_cell_angle_beta   90.044
_cell_angle_gamma   89.916
_symmetry_Int_Tables_number   1
_cell_volume   512.273
_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
  Fe  Fe0  1  0.125  0.875  0.375  1.0
  Fe  Fe1  1  0.375  0.125  0.875  1.0
  Fe  Fe2  1  0.625  0.625  0.625  1.0
  Fe  Fe3  1  0.875  0.375  0.125  1.0
  Co  Co4  1  0.126  0.125  0.625  1.0
  Co  Co5  1  0.125  0.375  0.876  1.0
  Co  Co6  1  0.124  0.625  0.126  1.0
  Co  Co7  1  0.376  0.375  0.625  1.0
  Co  Co8  1  0.375  0.626  0.375  1.0
  Co  Co9  1  0.374  0.876  0.125  1.0
  Co  Co10  1  0.626  0.375  0.375  1.0
  Co  Co11  1  0.625  0.125  0.124  1.0
  Co  Co12  1  0.624  0.875  0.874  1.0
  Co  Co13  1  0.876  0.125  0.375  1.0
  Co  Co14  1  0.875  0.874  0.625  1.0
  Co  Co15  1  0.874  0.624  0.875  1.0
  O  O16  1  0.112  0.110  0.389  1.0
  O  O17  1  0.112  0.888  0.610  1.0
  O  O18  1  0.107  0.607  0.893  1.0
  O  O19  1  0.140  0.139  0.861  1.0
  O  O20  1  0.110  0.389  0.112  1.0
  O  O21  1  0.143  0.357  0.643  1.0
  O  O22  1  0.139  0.640  0.362  1.0
  O  O23  1  0.137  0.861  0.141  1.0
  O  O24  1  0.362  0.139  0.640  1.0
  O  O25  1  0.362  0.360  0.861  1.0
  O  O26  1  0.357  0.643  0.143  1.0
  O  O27  1  0.390  0.611  0.611  1.0
  O  O28  1  0.360  0.862  0.361  1.0
  O  O29  1  0.393  0.393  0.393  1.0
  O  O30  1  0.389  0.112  0.110  1.0
  O  O31  1  0.387  0.891  0.889  1.0
  O  O32  1  0.612  0.390  0.611  1.0
  O  O33  1  0.612  0.611  0.390  1.0
  O  O34  1  0.607  0.893  0.107  1.0
  O  O35  1  0.640  0.361  0.139  1.0
  O  O36  1  0.610  0.111  0.888  1.0
  O  O37  1  0.643  0.143  0.357  1.0
  O  O38  1  0.639  0.860  0.638  1.0
  O  O39  1  0.637  0.639  0.859  1.0
  O  O40  1  0.862  0.361  0.360  1.0
  O  O41  1  0.862  0.140  0.138  1.0
  O  O42  1  0.857  0.857  0.857  1.0
  O  O43  1  0.890  0.889  0.389  1.0
  O  O44  1  0.860  0.638  0.639  1.0
  O  O45  1  0.893  0.107  0.607  1.0
  O  O46  1  0.889  0.388  0.890  1.0
  O  O47  1  0.887  0.610  0.111  1.0
[/CIF]
.