The structure described by MgCo4NiO8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-16°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with six equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-14°. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with six equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-14°. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Co site, Co(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(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. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form NiO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-16°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Co(3), one Co(4), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mg(1), one Co(1), one Co(2), one Co(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Co(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Co(4) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the seventh O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), one Co(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the eighth O site, O(8) is bonded in a see-saw-like geometry to one Mg(1), one Co(3), one Co(4), and one Ni(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4NiO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.761
_cell_length_b   5.865
_cell_length_c   5.929
_cell_angle_alpha   92.100
_cell_angle_beta   62.189
_cell_angle_gamma   60.250
_symmetry_Int_Tables_number   1
_cell_volume   144.139
_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  0.518  0.010  0.496  1.0
  Co  Co1  1  0.015  0.508  0.496  1.0
  Co  Co2  1  0.017  0.009  0.994  1.0
  Co  Co3  1  0.518  0.009  0.995  1.0
  Co  Co4  1  0.017  0.509  0.995  1.0
  Ni  Ni5  1  0.516  0.511  0.998  1.0
  O  O6  1  0.471  0.261  0.794  1.0
  O  O7  1  0.017  0.275  0.769  1.0
  O  O8  1  0.498  0.783  0.769  1.0
  O  O9  1  0.984  0.754  0.786  1.0
  O  O10  1  0.051  0.263  0.203  1.0
  O  O11  1  0.536  0.236  0.222  1.0
  O  O12  1  0.017  0.744  0.223  1.0
  O  O13  1  0.563  0.759  0.198  1.0
[/CIF]
.
The structure described by MgCo4NiO8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-16°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with six equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-14°. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with six equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-14°. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Co site, Co(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form CoO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(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. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form NiO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-16°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Co(3), one Co(4), and one Ni(1) atom. In the second O site, O(2) is bonded to one Mg(1), one Co(1), one Co(2), one Co(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Co(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Co(1), one Co(2), one Co(3), and one Co(4) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(2), one Co(3), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the seventh O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), one Co(4), and one Ni(1) atom to form a mixture of corner and edge-sharing OMgCo3Ni square pyramids. In the eighth O site, O(8) is bonded in a see-saw-like geometry to one Mg(1), one Co(3), one Co(4), and one Ni(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4NiO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.761
_cell_length_b   5.865
_cell_length_c   5.929
_cell_angle_alpha   92.100
_cell_angle_beta   62.189
_cell_angle_gamma   60.250
_symmetry_Int_Tables_number   1
_cell_volume   144.139
_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  0.518  0.010  0.496  1.0
  Co  Co1  1  0.015  0.508  0.496  1.0
  Co  Co2  1  0.017  0.009  0.994  1.0
  Co  Co3  1  0.518  0.009  0.995  1.0
  Co  Co4  1  0.017  0.509  0.995  1.0
  Ni  Ni5  1  0.516  0.511  0.998  1.0
  O  O6  1  0.471  0.261  0.794  1.0
  O  O7  1  0.017  0.275  0.769  1.0
  O  O8  1  0.498  0.783  0.769  1.0
  O  O9  1  0.984  0.754  0.786  1.0
  O  O10  1  0.051  0.263  0.203  1.0
  O  O11  1  0.536  0.236  0.222  1.0
  O  O12  1  0.017  0.744  0.223  1.0
  O  O13  1  0.563  0.759  0.198  1.0
[/CIF]
.