The compound described by MgCo5O8 is Spinel-like structured and crystallizes in the trigonal R3 space group. Mg(1) is bonded to one O(4) and three equivalent O(3) atoms to form MgO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra and corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-66°. 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(3) atoms to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CoO4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-66°. In the third Co site, Co(3) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra, and edges with six equivalent Co(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Co(2), one Co(3), and two equivalent Co(1) atoms to form distorted OCo4 trigonal pyramids that share  a cornercorner with one O(2)Co4 tetrahedra, corners with two equivalent O(4)MgCo3 tetrahedra, corners with two equivalent O(1)Co4 trigonal pyramids,  an edgeedge with one O(2)Co4 tetrahedra, and edges with two equivalent O(1)Co4 trigonal pyramids. In the second O site, O(2) is bonded to one Co(2) and three equivalent Co(1) atoms to form OCo4 tetrahedra that share corners with three equivalent O(4)MgCo3 tetrahedra, corners with three equivalent O(1)Co4 trigonal pyramids, and edges with three equivalent O(1)Co4 trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded to one Mg(1) and three equivalent Co(1) atoms to form corner-sharing OMgCo3 tetrahedra. is represented by the CIF file [CIF]
data_MgCo5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.873
_cell_length_b   5.866
_cell_length_c   5.875
_cell_angle_alpha   89.983
_cell_angle_beta   60.047
_cell_angle_gamma   60.027
_symmetry_Int_Tables_number   1
_cell_volume   143.322
_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  0.752  0.124  0.871  1.0
  Co  Co1  1  0.512  0.492  0.481  1.0
  Co  Co2  1  0.511  0.995  0.481  1.0
  Co  Co3  1  0.272  0.864  0.091  1.0
  Co  Co4  1  0.014  0.494  0.481  1.0
  Co  Co5  1  0.014  0.493  0.978  1.0
  O  O6  1  0.032  0.695  0.224  1.0
  O  O7  1  0.969  0.273  0.225  1.0
  O  O8  1  0.549  0.725  0.676  1.0
  O  O9  1  0.549  0.757  0.224  1.0
  O  O10  1  0.476  0.230  0.735  1.0
  O  O11  1  0.475  0.263  0.286  1.0
  O  O12  1  0.058  0.712  0.734  1.0
  O  O13  1  0.995  0.293  0.734  1.0
[/CIF]
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The compound described by MgCo5O8 is Spinel-like structured and crystallizes in the trigonal R3 space group. Mg(1) is bonded to one O(4) and three equivalent O(3) atoms to form MgO4 tetrahedra that share corners with three equivalent Co(3)O6 octahedra and corners with nine equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-66°. 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(3) atoms to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Co(1)O6 octahedra. In the second Co site, Co(2) is bonded to one O(2) and three equivalent O(1) atoms to form corner-sharing CoO4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-66°. In the third Co site, Co(3) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form CoO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra, and edges with six equivalent Co(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Co(2), one Co(3), and two equivalent Co(1) atoms to form distorted OCo4 trigonal pyramids that share  a cornercorner with one O(2)Co4 tetrahedra, corners with two equivalent O(4)MgCo3 tetrahedra, corners with two equivalent O(1)Co4 trigonal pyramids,  an edgeedge with one O(2)Co4 tetrahedra, and edges with two equivalent O(1)Co4 trigonal pyramids. In the second O site, O(2) is bonded to one Co(2) and three equivalent Co(1) atoms to form OCo4 tetrahedra that share corners with three equivalent O(4)MgCo3 tetrahedra, corners with three equivalent O(1)Co4 trigonal pyramids, and edges with three equivalent O(1)Co4 trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded to one Mg(1) and three equivalent Co(1) atoms to form corner-sharing OMgCo3 tetrahedra. is represented by the CIF file [CIF]
data_MgCo5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.873
_cell_length_b   5.866
_cell_length_c   5.875
_cell_angle_alpha   89.983
_cell_angle_beta   60.047
_cell_angle_gamma   60.027
_symmetry_Int_Tables_number   1
_cell_volume   143.322
_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  0.752  0.124  0.871  1.0
  Co  Co1  1  0.512  0.492  0.481  1.0
  Co  Co2  1  0.511  0.995  0.481  1.0
  Co  Co3  1  0.272  0.864  0.091  1.0
  Co  Co4  1  0.014  0.494  0.481  1.0
  Co  Co5  1  0.014  0.493  0.978  1.0
  O  O6  1  0.032  0.695  0.224  1.0
  O  O7  1  0.969  0.273  0.225  1.0
  O  O8  1  0.549  0.725  0.676  1.0
  O  O9  1  0.549  0.757  0.224  1.0
  O  O10  1  0.476  0.230  0.735  1.0
  O  O11  1  0.475  0.263  0.286  1.0
  O  O12  1  0.058  0.712  0.734  1.0
  O  O13  1  0.995  0.293  0.734  1.0
[/CIF]
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