The structure described by MgCo4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with four equivalent Co(3)O6 octahedra, corners with six equivalent Ni(1)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 21-67°. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted CoO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra, corners with six equivalent Co(2)O5 square pyramids, edges with two equivalent Co(3)O6 octahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Co site, Co(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Ni(1)O6 octahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Co(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-74°. In the third Co site, Co(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CoO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra, corners with six equivalent Co(2)O5 square pyramids, corners with four equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. Ni(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Co(2)O5 square pyramids,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCo2Ni2 trigonal bipyramids that share corners with four equivalent O(2)Co3Ni tetrahedra, corners with two equivalent O(3)MgCo3Ni trigonal bipyramids,  an edgeedge with one O(1)MgCo2Ni2 trigonal bipyramid, edges with two equivalent O(3)MgCo3Ni trigonal bipyramids, and  a faceface with one O(1)MgCo2Ni2 trigonal bipyramid. In the second O site, O(2) is bonded to one Co(1), two equivalent Co(2), and one Ni(1) atom to form distorted OCo3Ni tetrahedra that share  a cornercorner with one O(2)Co3Ni tetrahedra, corners with four equivalent O(1)MgCo2Ni2 trigonal bipyramids, corners with five equivalent O(3)MgCo3Ni trigonal bipyramids, and  an edgeedge with one O(2)Co3Ni tetrahedra. In the third O site, O(3) is bonded to one Mg(1), one Co(3), two equivalent Co(2), and one Ni(1) atom to form OMgCo3Ni trigonal bipyramids that share corners with five equivalent O(2)Co3Ni tetrahedra,  a cornercorner with one O(3)MgCo3Ni trigonal bipyramid, corners with two equivalent O(1)MgCo2Ni2 trigonal bipyramids, edges with two equivalent O(1)MgCo2Ni2 trigonal bipyramids, and  a faceface with one O(3)MgCo3Ni trigonal bipyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.960
_cell_length_b   5.841
_cell_length_c   5.960
_cell_angle_alpha   60.658
_cell_angle_beta   65.483
_cell_angle_gamma   60.658
_symmetry_Int_Tables_number   1
_cell_volume   153.440
_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  0.306  0.944  0.306  1.0
  Co  Co1  1  0.995  0.255  0.995  1.0
  Co  Co2  1  0.555  0.958  0.555  1.0
  Co  Co3  1  0.555  0.432  0.555  1.0
  Co  Co4  1  0.956  0.794  0.956  1.0
  Ni  Ni5  1  0.023  0.498  0.482  1.0
  Ni  Ni6  1  0.482  0.498  0.023  1.0
  O  O7  1  0.181  0.344  0.181  1.0
  O  O8  1  0.321  0.240  0.699  1.0
  O  O9  1  0.181  0.795  0.181  1.0
  O  O10  1  0.699  0.240  0.321  1.0
  O  O11  1  0.321  0.743  0.694  1.0
  O  O12  1  0.793  0.228  0.793  1.0
  O  O13  1  0.694  0.743  0.321  1.0
  O  O14  1  0.793  0.687  0.793  1.0
[/CIF]
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The structure described by MgCo4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with four equivalent Co(3)O6 octahedra, corners with six equivalent Ni(1)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 21-67°. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted CoO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra, corners with six equivalent Co(2)O5 square pyramids, edges with two equivalent Co(3)O6 octahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Co site, Co(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Ni(1)O6 octahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Co(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-74°. In the third Co site, Co(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CoO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra, corners with six equivalent Co(2)O5 square pyramids, corners with four equivalent Mg(1)O4 tetrahedra, edges with two equivalent Co(1)O6 octahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. Ni(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, corners with three equivalent Mg(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Co(2)O5 square pyramids,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCo2Ni2 trigonal bipyramids that share corners with four equivalent O(2)Co3Ni tetrahedra, corners with two equivalent O(3)MgCo3Ni trigonal bipyramids,  an edgeedge with one O(1)MgCo2Ni2 trigonal bipyramid, edges with two equivalent O(3)MgCo3Ni trigonal bipyramids, and  a faceface with one O(1)MgCo2Ni2 trigonal bipyramid. In the second O site, O(2) is bonded to one Co(1), two equivalent Co(2), and one Ni(1) atom to form distorted OCo3Ni tetrahedra that share  a cornercorner with one O(2)Co3Ni tetrahedra, corners with four equivalent O(1)MgCo2Ni2 trigonal bipyramids, corners with five equivalent O(3)MgCo3Ni trigonal bipyramids, and  an edgeedge with one O(2)Co3Ni tetrahedra. In the third O site, O(3) is bonded to one Mg(1), one Co(3), two equivalent Co(2), and one Ni(1) atom to form OMgCo3Ni trigonal bipyramids that share corners with five equivalent O(2)Co3Ni tetrahedra,  a cornercorner with one O(3)MgCo3Ni trigonal bipyramid, corners with two equivalent O(1)MgCo2Ni2 trigonal bipyramids, edges with two equivalent O(1)MgCo2Ni2 trigonal bipyramids, and  a faceface with one O(3)MgCo3Ni trigonal bipyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Co(1), one Co(2), one Co(3), and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.960
_cell_length_b   5.841
_cell_length_c   5.960
_cell_angle_alpha   60.658
_cell_angle_beta   65.483
_cell_angle_gamma   60.658
_symmetry_Int_Tables_number   1
_cell_volume   153.440
_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  0.306  0.944  0.306  1.0
  Co  Co1  1  0.995  0.255  0.995  1.0
  Co  Co2  1  0.555  0.958  0.555  1.0
  Co  Co3  1  0.555  0.432  0.555  1.0
  Co  Co4  1  0.956  0.794  0.956  1.0
  Ni  Ni5  1  0.023  0.498  0.482  1.0
  Ni  Ni6  1  0.482  0.498  0.023  1.0
  O  O7  1  0.181  0.344  0.181  1.0
  O  O8  1  0.321  0.240  0.699  1.0
  O  O9  1  0.181  0.795  0.181  1.0
  O  O10  1  0.699  0.240  0.321  1.0
  O  O11  1  0.321  0.743  0.694  1.0
  O  O12  1  0.793  0.228  0.793  1.0
  O  O13  1  0.694  0.743  0.321  1.0
  O  O14  1  0.793  0.687  0.793  1.0
[/CIF]
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