The compound described by MgCu2(NiO2)4 crystallizes in the cubic F-43m space group. Mg(1) is bonded to four equivalent Ni(1) and four equivalent O(2) atoms to form distorted MgNi4O4 tetrahedra that share corners with four equivalent Cu(1)O4 tetrahedra. Ni(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent O(1), and three equivalent O(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent O(2) atoms to form CuO4 tetrahedra that share corners with four equivalent Mg(1)Ni4O4 tetrahedra. In the second Cu site, Cu(2) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to three equivalent Ni(1) and one Cu(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), three equivalent Ni(1), and one Cu(1) atom. is represented by the CIF file [CIF]
data_MgCu2(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.229
_cell_length_b   6.230
_cell_length_c   6.227
_cell_angle_alpha   60.011
_cell_angle_beta   90.000
_cell_angle_gamma   120.020
_symmetry_Int_Tables_number   1
_cell_volume   170.863
_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  0.750  0.500  0.750  1.0
  Cu  Cu1  1  1.000  1.000  0.000  1.0
  Cu  Cu2  1  0.250  0.500  0.250  1.0
  Ni  Ni3  1  0.607  0.214  0.179  1.0
  Ni  Ni4  1  0.607  0.214  0.607  1.0
  Ni  Ni5  1  0.607  0.786  0.607  1.0
  Ni  Ni6  1  0.179  0.786  0.607  1.0
  O  O7  1  0.853  0.235  0.382  1.0
  O  O8  1  0.382  0.235  0.382  1.0
  O  O9  1  0.872  0.255  0.872  1.0
  O  O10  1  0.872  0.745  0.383  1.0
  O  O11  1  0.383  0.255  0.872  1.0
  O  O12  1  0.872  0.745  0.872  1.0
  O  O13  1  0.382  0.765  0.382  1.0
  O  O14  1  0.382  0.765  0.853  1.0
[/CIF]
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The compound described by MgCu2(NiO2)4 crystallizes in the cubic F-43m space group. Mg(1) is bonded to four equivalent Ni(1) and four equivalent O(2) atoms to form distorted MgNi4O4 tetrahedra that share corners with four equivalent Cu(1)O4 tetrahedra. Ni(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent O(1), and three equivalent O(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent O(2) atoms to form CuO4 tetrahedra that share corners with four equivalent Mg(1)Ni4O4 tetrahedra. In the second Cu site, Cu(2) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to three equivalent Ni(1) and one Cu(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), three equivalent Ni(1), and one Cu(1) atom. is represented by the CIF file [CIF]
data_MgCu2(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.229
_cell_length_b   6.230
_cell_length_c   6.227
_cell_angle_alpha   60.011
_cell_angle_beta   90.000
_cell_angle_gamma   120.020
_symmetry_Int_Tables_number   1
_cell_volume   170.863
_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  0.750  0.500  0.750  1.0
  Cu  Cu1  1  1.000  1.000  0.000  1.0
  Cu  Cu2  1  0.250  0.500  0.250  1.0
  Ni  Ni3  1  0.607  0.214  0.179  1.0
  Ni  Ni4  1  0.607  0.214  0.607  1.0
  Ni  Ni5  1  0.607  0.786  0.607  1.0
  Ni  Ni6  1  0.179  0.786  0.607  1.0
  O  O7  1  0.853  0.235  0.382  1.0
  O  O8  1  0.382  0.235  0.382  1.0
  O  O9  1  0.872  0.255  0.872  1.0
  O  O10  1  0.872  0.745  0.383  1.0
  O  O11  1  0.383  0.255  0.872  1.0
  O  O12  1  0.872  0.745  0.872  1.0
  O  O13  1  0.382  0.765  0.382  1.0
  O  O14  1  0.382  0.765  0.853  1.0
[/CIF]
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