The structure described by MgFe2(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 Fe(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(2) atoms to form FeO4 tetrahedra that share corners with four equivalent Mg(1)Ni4O4 tetrahedra. In the second Fe site, Fe(2) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. 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 O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Fe(2) and three equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(1), and three equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe2(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.249
_cell_length_b   6.250
_cell_length_c   6.250
_cell_angle_alpha   59.995
_cell_angle_beta   60.003
_cell_angle_gamma   59.990
_symmetry_Int_Tables_number   1
_cell_volume   172.585
_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  0.375  0.375  0.375  1.0
  Fe  Fe1  1  0.125  0.125  0.125  1.0
  Fe  Fe2  1  0.875  0.875  0.875  1.0
  Ni  Ni3  1  0.519  0.519  0.944  1.0
  Ni  Ni4  1  0.944  0.519  0.519  1.0
  Ni  Ni5  1  0.519  0.944  0.519  1.0
  Ni  Ni6  1  0.519  0.519  0.519  1.0
  O  O7  1  0.261  0.746  0.746  1.0
  O  O8  1  0.252  0.744  0.252  1.0
  O  O9  1  0.744  0.252  0.252  1.0
  O  O10  1  0.252  0.252  0.252  1.0
  O  O11  1  0.252  0.252  0.743  1.0
  O  O12  1  0.746  0.261  0.746  1.0
  O  O13  1  0.746  0.746  0.262  1.0
  O  O14  1  0.746  0.746  0.746  1.0
[/CIF]
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The structure described by MgFe2(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 Fe(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(2) atoms to form FeO4 tetrahedra that share corners with four equivalent Mg(1)Ni4O4 tetrahedra. In the second Fe site, Fe(2) is bonded in a tetrahedral geometry to four equivalent O(1) atoms. 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 O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Fe(2) and three equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(1), and three equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe2(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.249
_cell_length_b   6.250
_cell_length_c   6.250
_cell_angle_alpha   59.995
_cell_angle_beta   60.003
_cell_angle_gamma   59.990
_symmetry_Int_Tables_number   1
_cell_volume   172.585
_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  0.375  0.375  0.375  1.0
  Fe  Fe1  1  0.125  0.125  0.125  1.0
  Fe  Fe2  1  0.875  0.875  0.875  1.0
  Ni  Ni3  1  0.519  0.519  0.944  1.0
  Ni  Ni4  1  0.944  0.519  0.519  1.0
  Ni  Ni5  1  0.519  0.944  0.519  1.0
  Ni  Ni6  1  0.519  0.519  0.519  1.0
  O  O7  1  0.261  0.746  0.746  1.0
  O  O8  1  0.252  0.744  0.252  1.0
  O  O9  1  0.744  0.252  0.252  1.0
  O  O10  1  0.252  0.252  0.252  1.0
  O  O11  1  0.252  0.252  0.743  1.0
  O  O12  1  0.746  0.261  0.746  1.0
  O  O13  1  0.746  0.746  0.262  1.0
  O  O14  1  0.746  0.746  0.746  1.0
[/CIF]
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