The material structure described by Ni2FeO4 is Spinel structured and crystallizes in the orthorhombic Imma space group. Fe(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. 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(1), one Ni(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_Fe(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.876
_cell_length_b   5.926
_cell_length_c   5.932
_cell_angle_alpha   120.033
_cell_angle_beta   90.001
_cell_angle_gamma   119.721
_symmetry_Int_Tables_number   1
_cell_volume   146.572
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.370  0.241  0.120  1.0
  Fe  Fe1  1  0.630  0.759  0.880  1.0
  Ni  Ni2  1  0.000  0.000  0.500  1.0
  Ni  Ni3  1  0.500  0.000  0.500  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  Ni  Ni5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.758  0.015  0.270  1.0
  O  O7  1  0.238  0.508  0.254  1.0
  O  O8  1  0.242  0.985  0.730  1.0
  O  O9  1  0.769  0.508  0.254  1.0
  O  O10  1  0.242  0.985  0.254  1.0
  O  O11  1  0.762  0.492  0.746  1.0
  O  O12  1  0.758  0.015  0.746  1.0
  O  O13  1  0.231  0.492  0.746  1.0
[/CIF]
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The material structure described by Ni2FeO4 is Spinel structured and crystallizes in the orthorhombic Imma space group. Fe(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. 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(1), one Ni(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_Fe(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.876
_cell_length_b   5.926
_cell_length_c   5.932
_cell_angle_alpha   120.033
_cell_angle_beta   90.001
_cell_angle_gamma   119.721
_symmetry_Int_Tables_number   1
_cell_volume   146.572
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.370  0.241  0.120  1.0
  Fe  Fe1  1  0.630  0.759  0.880  1.0
  Ni  Ni2  1  0.000  0.000  0.500  1.0
  Ni  Ni3  1  0.500  0.000  0.500  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  Ni  Ni5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.758  0.015  0.270  1.0
  O  O7  1  0.238  0.508  0.254  1.0
  O  O8  1  0.242  0.985  0.730  1.0
  O  O9  1  0.769  0.508  0.254  1.0
  O  O10  1  0.242  0.985  0.254  1.0
  O  O11  1  0.762  0.492  0.746  1.0
  O  O12  1  0.758  0.015  0.746  1.0
  O  O13  1  0.231  0.492  0.746  1.0
[/CIF]
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