The crystal structure described by MgCo4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing CoO4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and edges with two equivalent Co(2)O5 square pyramids. In the third Co site, Co(3) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing CoO4 tetrahedra. Ni(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Co(1), one Co(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(1), two equivalent Co(2), and one Ni(1) atom. In the third O site, O(3) is bonded to one Mg(1), one Co(3), and two equivalent Co(2) atoms to form distorted OMgCo3 tetrahedra that share  a cornercorner with one O(3)MgCo3 tetrahedra, corners with four equivalent O(4)MgCoNi2 tetrahedra, and  a faceface with one O(3)MgCo3 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCoNi2 tetrahedra that share  a cornercorner with one O(4)MgCoNi2 tetrahedra, corners with four equivalent O(3)MgCo3 tetrahedra, and  a faceface with one O(4)MgCoNi2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.683
_cell_length_b   5.792
_cell_length_c   6.683
_cell_angle_alpha   64.324
_cell_angle_beta   51.170
_cell_angle_gamma   64.324
_symmetry_Int_Tables_number   1
_cell_volume   176.759
_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  0.627  0.623  0.627  1.0
  Co  Co1  1  0.128  0.122  0.128  1.0
  Co  Co2  1  0.455  0.055  0.455  1.0
  Co  Co3  1  0.455  0.534  0.455  1.0
  Co  Co4  1  0.874  0.876  0.874  1.0
  Ni  Ni5  1  0.059  0.453  0.535  1.0
  Ni  Ni6  1  0.535  0.453  0.059  1.0
  O  O7  1  0.258  0.258  0.258  1.0
  O  O8  1  0.251  0.261  0.728  1.0
  O  O9  1  0.258  0.726  0.258  1.0
  O  O10  1  0.728  0.261  0.251  1.0
  O  O11  1  0.251  0.770  0.709  1.0
  O  O12  1  0.769  0.251  0.769  1.0
  O  O13  1  0.709  0.770  0.251  1.0
  O  O14  1  0.769  0.710  0.769  1.0
[/CIF]
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The crystal structure described by MgCo4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing CoO4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Co(3)O4 tetrahedra, corners with three equivalent Co(1)O4 tetrahedra, and edges with two equivalent Co(2)O5 square pyramids. In the third Co site, Co(3) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing CoO4 tetrahedra. Ni(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Co(1), one Co(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Co(1), two equivalent Co(2), and one Ni(1) atom. In the third O site, O(3) is bonded to one Mg(1), one Co(3), and two equivalent Co(2) atoms to form distorted OMgCo3 tetrahedra that share  a cornercorner with one O(3)MgCo3 tetrahedra, corners with four equivalent O(4)MgCoNi2 tetrahedra, and  a faceface with one O(3)MgCo3 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCoNi2 tetrahedra that share  a cornercorner with one O(4)MgCoNi2 tetrahedra, corners with four equivalent O(3)MgCo3 tetrahedra, and  a faceface with one O(4)MgCoNi2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.683
_cell_length_b   5.792
_cell_length_c   6.683
_cell_angle_alpha   64.324
_cell_angle_beta   51.170
_cell_angle_gamma   64.324
_symmetry_Int_Tables_number   1
_cell_volume   176.759
_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  0.627  0.623  0.627  1.0
  Co  Co1  1  0.128  0.122  0.128  1.0
  Co  Co2  1  0.455  0.055  0.455  1.0
  Co  Co3  1  0.455  0.534  0.455  1.0
  Co  Co4  1  0.874  0.876  0.874  1.0
  Ni  Ni5  1  0.059  0.453  0.535  1.0
  Ni  Ni6  1  0.535  0.453  0.059  1.0
  O  O7  1  0.258  0.258  0.258  1.0
  O  O8  1  0.251  0.261  0.728  1.0
  O  O9  1  0.258  0.726  0.258  1.0
  O  O10  1  0.728  0.261  0.251  1.0
  O  O11  1  0.251  0.770  0.709  1.0
  O  O12  1  0.769  0.251  0.769  1.0
  O  O13  1  0.709  0.770  0.251  1.0
  O  O14  1  0.769  0.710  0.769  1.0
[/CIF]
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