The structure described by MgFe4CoO8 is Spinel-derived structured and crystallizes in the trigonal R3m space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and edges with six equivalent Fe(2)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2) and three equivalent O(1) atoms to form FeO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Fe site, Fe(2) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. Co(1) is bonded to one O(4) and three equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(2)Fe4 trigonal pyramid, corners with two equivalent O(1)MgFe3 trigonal pyramids, corners with seven equivalent O(3)MgFe2Co trigonal pyramids,  an edgeedge with one O(2)Fe4 trigonal pyramid, and edges with two equivalent O(1)MgFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Fe(1) and three equivalent Fe(2) atoms to form distorted OFe4 trigonal pyramids that share corners with three equivalent O(1)MgFe3 trigonal pyramids, corners with six equivalent O(3)MgFe2Co trigonal pyramids, and edges with three equivalent O(1)MgFe3 trigonal pyramids. In the third O site, O(3) is bonded to one Mg(1), two equivalent Fe(2), and one Co(1) atom to form distorted OMgFe2Co trigonal pyramids that share corners with two equivalent O(2)Fe4 trigonal pyramids, corners with two equivalent O(3)MgFe2Co trigonal pyramids, corners with seven equivalent O(1)MgFe3 trigonal pyramids, and edges with two equivalent O(3)MgFe2Co trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Fe(2) and one Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4CoO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.047
_cell_length_b   6.047
_cell_length_c   6.047
_cell_angle_alpha   59.804
_cell_angle_beta   59.804
_cell_angle_gamma   59.804
_symmetry_Int_Tables_number   1
_cell_volume   155.695
_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
  Mg  Mg0  1  0.001  0.001  0.001  1.0
  Fe  Fe1  1  0.623  0.623  0.623  1.0
  Fe  Fe2  1  0.494  0.001  0.001  1.0
  Fe  Fe3  1  0.001  0.001  0.494  1.0
  Fe  Fe4  1  0.001  0.494  0.001  1.0
  Co  Co5  1  0.377  0.377  0.377  1.0
  O  O6  1  0.230  0.754  0.754  1.0
  O  O7  1  0.754  0.754  0.230  1.0
  O  O8  1  0.754  0.230  0.754  1.0
  O  O9  1  0.757  0.757  0.757  1.0
  O  O10  1  0.781  0.243  0.243  1.0
  O  O11  1  0.243  0.243  0.781  1.0
  O  O12  1  0.243  0.781  0.243  1.0
  O  O13  1  0.241  0.241  0.241  1.0
[/CIF]
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The structure described by MgFe4CoO8 is Spinel-derived structured and crystallizes in the trigonal R3m space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form MgO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and edges with six equivalent Fe(2)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2) and three equivalent O(1) atoms to form FeO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Fe site, Fe(2) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. Co(1) is bonded to one O(4) and three equivalent O(3) atoms to form CoO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(2)Fe4 trigonal pyramid, corners with two equivalent O(1)MgFe3 trigonal pyramids, corners with seven equivalent O(3)MgFe2Co trigonal pyramids,  an edgeedge with one O(2)Fe4 trigonal pyramid, and edges with two equivalent O(1)MgFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Fe(1) and three equivalent Fe(2) atoms to form distorted OFe4 trigonal pyramids that share corners with three equivalent O(1)MgFe3 trigonal pyramids, corners with six equivalent O(3)MgFe2Co trigonal pyramids, and edges with three equivalent O(1)MgFe3 trigonal pyramids. In the third O site, O(3) is bonded to one Mg(1), two equivalent Fe(2), and one Co(1) atom to form distorted OMgFe2Co trigonal pyramids that share corners with two equivalent O(2)Fe4 trigonal pyramids, corners with two equivalent O(3)MgFe2Co trigonal pyramids, corners with seven equivalent O(1)MgFe3 trigonal pyramids, and edges with two equivalent O(3)MgFe2Co trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Fe(2) and one Co(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4CoO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.047
_cell_length_b   6.047
_cell_length_c   6.047
_cell_angle_alpha   59.804
_cell_angle_beta   59.804
_cell_angle_gamma   59.804
_symmetry_Int_Tables_number   1
_cell_volume   155.695
_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
  Mg  Mg0  1  0.001  0.001  0.001  1.0
  Fe  Fe1  1  0.623  0.623  0.623  1.0
  Fe  Fe2  1  0.494  0.001  0.001  1.0
  Fe  Fe3  1  0.001  0.001  0.494  1.0
  Fe  Fe4  1  0.001  0.494  0.001  1.0
  Co  Co5  1  0.377  0.377  0.377  1.0
  O  O6  1  0.230  0.754  0.754  1.0
  O  O7  1  0.754  0.754  0.230  1.0
  O  O8  1  0.754  0.230  0.754  1.0
  O  O9  1  0.757  0.757  0.757  1.0
  O  O10  1  0.781  0.243  0.243  1.0
  O  O11  1  0.243  0.243  0.781  1.0
  O  O12  1  0.243  0.781  0.243  1.0
  O  O13  1  0.241  0.241  0.241  1.0
[/CIF]
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