The compound described by MgCo(NiO2)4 is Corundum-derived structured and crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(4), one O(6), and two equivalent O(2) atoms. Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Ni(2)O6 octahedra and edges with four equivalent Ni(1)O6 octahedra. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form NiO6 octahedra that share edges with two equivalent Co(1)O6 octahedra and edges with four equivalent Ni(1)O6 octahedra. In the third Ni site, Ni(3) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Co(1), one Ni(1), one Ni(2), and one Ni(3) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), one Ni(1), and one Ni(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Co(1), one Ni(3), and two equivalent Ni(1) atoms. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), and two equivalent Ni(1) atoms. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ni(2), one Ni(3), and two equivalent Ni(1) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ni(2), and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MgCo(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.432
_cell_length_b   11.432
_cell_length_c   17.559
_cell_angle_alpha   16.828
_cell_angle_beta   16.828
_cell_angle_gamma   29.822
_symmetry_Int_Tables_number   1
_cell_volume   156.658
_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  0.627  0.028  1.0
  Co  Co1  1  0.499  0.499  0.010  1.0
  Ni  Ni2  1  0.002  0.503  0.006  1.0
  Ni  Ni3  1  0.999  0.999  0.010  1.0
  Ni  Ni4  1  0.374  0.374  0.990  1.0
  Ni  Ni5  1  0.503  0.002  0.006  1.0
  O  O6  1  0.136  0.691  0.523  1.0
  O  O7  1  0.860  0.311  0.495  1.0
  O  O8  1  0.794  0.794  0.545  1.0
  O  O9  1  0.208  0.208  0.468  1.0
  O  O10  1  0.604  0.604  0.597  1.0
  O  O11  1  0.393  0.393  0.425  1.0
  O  O12  1  0.691  0.136  0.523  1.0
  O  O13  1  0.311  0.860  0.495  1.0
[/CIF]
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The compound described by MgCo(NiO2)4 is Corundum-derived structured and crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(4), one O(6), and two equivalent O(2) atoms. Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form CoO6 octahedra that share edges with two equivalent Ni(2)O6 octahedra and edges with four equivalent Ni(1)O6 octahedra. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form NiO6 octahedra that share edges with two equivalent Co(1)O6 octahedra and edges with four equivalent Ni(1)O6 octahedra. In the third Ni site, Ni(3) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Co(1), one Ni(1), one Ni(2), and one Ni(3) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), one Ni(1), and one Ni(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Co(1), one Ni(3), and two equivalent Ni(1) atoms. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), and two equivalent Ni(1) atoms. In the fifth O site, O(5) is bonded in a see-saw-like geometry to one Ni(2), one Ni(3), and two equivalent Ni(1) atoms. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ni(2), and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_MgCo(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.432
_cell_length_b   11.432
_cell_length_c   17.559
_cell_angle_alpha   16.828
_cell_angle_beta   16.828
_cell_angle_gamma   29.822
_symmetry_Int_Tables_number   1
_cell_volume   156.658
_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  0.627  0.028  1.0
  Co  Co1  1  0.499  0.499  0.010  1.0
  Ni  Ni2  1  0.002  0.503  0.006  1.0
  Ni  Ni3  1  0.999  0.999  0.010  1.0
  Ni  Ni4  1  0.374  0.374  0.990  1.0
  Ni  Ni5  1  0.503  0.002  0.006  1.0
  O  O6  1  0.136  0.691  0.523  1.0
  O  O7  1  0.860  0.311  0.495  1.0
  O  O8  1  0.794  0.794  0.545  1.0
  O  O9  1  0.208  0.208  0.468  1.0
  O  O10  1  0.604  0.604  0.597  1.0
  O  O11  1  0.393  0.393  0.425  1.0
  O  O12  1  0.691  0.136  0.523  1.0
  O  O13  1  0.311  0.860  0.495  1.0
[/CIF]
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