The material described by MgCo4(NiO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Co(3)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), and two equivalent O(2) atoms. In the second Co site, Co(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. In the third Co site, Co(3) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(2), and two equivalent Ni(1) atoms to form OCo2Ni2 tetrahedra that share corners with three equivalent O(3)MgCo2Ni2 square pyramids, corners with six equivalent O(2)MgCo3Ni square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra,  an edgeedge with one O(3)MgCo2Ni2 square pyramid, and edges with two equivalent O(2)MgCo3Ni square pyramids. In the second O site, O(2) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form OMgCo3Ni square pyramids that share  a cornercorner with one O(3)MgCo2Ni2 square pyramid, corners with five equivalent O(2)MgCo3Ni square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra, edges with three equivalent O(3)MgCo2Ni2 square pyramids, edges with three equivalent O(2)MgCo3Ni square pyramids, and  an edgeedge with one O(1)Co2Ni2 tetrahedra. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCo2Ni2 square pyramids that share corners with two equivalent O(2)MgCo3Ni square pyramids, corners with four equivalent O(3)MgCo2Ni2 square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra, edges with six equivalent O(2)MgCo3Ni square pyramids, and  an edgeedge with one O(1)Co2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.120
_cell_length_b   6.320
_cell_length_c   6.120
_cell_angle_alpha   55.950
_cell_angle_beta   56.555
_cell_angle_gamma   55.950
_symmetry_Int_Tables_number   1
_cell_volume   152.456
_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  0.000  0.000  0.000  1.0
  Co  Co1  1  0.170  0.129  0.170  1.0
  Co  Co2  1  0.500  0.000  0.500  1.0
  Co  Co3  1  0.500  0.500  0.500  1.0
  Co  Co4  1  0.830  0.871  0.830  1.0
  Ni  Ni5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.500  0.000  1.0
  O  O7  1  0.275  0.271  0.275  1.0
  O  O8  1  0.265  0.224  0.747  1.0
  O  O9  1  0.268  0.731  0.268  1.0
  O  O10  1  0.747  0.224  0.265  1.0
  O  O11  1  0.253  0.776  0.735  1.0
  O  O12  1  0.732  0.269  0.732  1.0
  O  O13  1  0.735  0.776  0.253  1.0
  O  O14  1  0.725  0.729  0.725  1.0
[/CIF]
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The material described by MgCo4(NiO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Co(3)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), and two equivalent O(2) atoms. In the second Co site, Co(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. In the third Co site, Co(3) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(2), and two equivalent Ni(1) atoms to form OCo2Ni2 tetrahedra that share corners with three equivalent O(3)MgCo2Ni2 square pyramids, corners with six equivalent O(2)MgCo3Ni square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra,  an edgeedge with one O(3)MgCo2Ni2 square pyramid, and edges with two equivalent O(2)MgCo3Ni square pyramids. In the second O site, O(2) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form OMgCo3Ni square pyramids that share  a cornercorner with one O(3)MgCo2Ni2 square pyramid, corners with five equivalent O(2)MgCo3Ni square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra, edges with three equivalent O(3)MgCo2Ni2 square pyramids, edges with three equivalent O(2)MgCo3Ni square pyramids, and  an edgeedge with one O(1)Co2Ni2 tetrahedra. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(3), and two equivalent Ni(1) atoms to form distorted OMgCo2Ni2 square pyramids that share corners with two equivalent O(2)MgCo3Ni square pyramids, corners with four equivalent O(3)MgCo2Ni2 square pyramids, corners with three equivalent O(1)Co2Ni2 tetrahedra, edges with six equivalent O(2)MgCo3Ni square pyramids, and  an edgeedge with one O(1)Co2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_MgCo4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.120
_cell_length_b   6.320
_cell_length_c   6.120
_cell_angle_alpha   55.950
_cell_angle_beta   56.555
_cell_angle_gamma   55.950
_symmetry_Int_Tables_number   1
_cell_volume   152.456
_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  0.000  0.000  0.000  1.0
  Co  Co1  1  0.170  0.129  0.170  1.0
  Co  Co2  1  0.500  0.000  0.500  1.0
  Co  Co3  1  0.500  0.500  0.500  1.0
  Co  Co4  1  0.830  0.871  0.830  1.0
  Ni  Ni5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.500  0.000  1.0
  O  O7  1  0.275  0.271  0.275  1.0
  O  O8  1  0.265  0.224  0.747  1.0
  O  O9  1  0.268  0.731  0.268  1.0
  O  O10  1  0.747  0.224  0.265  1.0
  O  O11  1  0.253  0.776  0.735  1.0
  O  O12  1  0.732  0.269  0.732  1.0
  O  O13  1  0.735  0.776  0.253  1.0
  O  O14  1  0.725  0.729  0.725  1.0
[/CIF]
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