The material structure described by NiFe2O4 is Spinel-like structured and crystallizes in the orthorhombic Imma space group. There are two inequivalent Fe sites. In the first Fe site, 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 Fe(2)O6 octahedra and corners with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. In the second Fe site, Fe(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. 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 Fe(2)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 Fe(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(2), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Fe2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.860
_cell_length_b   5.878
_cell_length_c   5.860
_cell_angle_alpha   59.901
_cell_angle_beta   60.240
_cell_angle_gamma   59.901
_symmetry_Int_Tables_number   1
_cell_volume   142.767
_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  0.998  0.002  0.998  1.0
  Fe  Fe1  1  0.252  0.248  0.252  1.0
  Fe  Fe2  1  0.625  0.125  0.625  1.0
  Fe  Fe3  1  0.625  0.625  0.625  1.0
  Ni  Ni4  1  0.125  0.625  0.625  1.0
  Ni  Ni5  1  0.625  0.625  0.125  1.0
  O  O6  1  0.383  0.376  0.383  1.0
  O  O7  1  0.386  0.377  0.859  1.0
  O  O8  1  0.383  0.857  0.383  1.0
  O  O9  1  0.859  0.377  0.386  1.0
  O  O10  1  0.391  0.873  0.864  1.0
  O  O11  1  0.867  0.393  0.867  1.0
  O  O12  1  0.864  0.873  0.391  1.0
  O  O13  1  0.867  0.874  0.867  1.0
[/CIF]
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The material structure described by NiFe2O4 is Spinel-like structured and crystallizes in the orthorhombic Imma space group. There are two inequivalent Fe sites. In the first Fe site, 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 Fe(2)O6 octahedra and corners with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. In the second Fe site, Fe(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. 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 Fe(2)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 Fe(2), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(2), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Fe2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.860
_cell_length_b   5.878
_cell_length_c   5.860
_cell_angle_alpha   59.901
_cell_angle_beta   60.240
_cell_angle_gamma   59.901
_symmetry_Int_Tables_number   1
_cell_volume   142.767
_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  0.998  0.002  0.998  1.0
  Fe  Fe1  1  0.252  0.248  0.252  1.0
  Fe  Fe2  1  0.625  0.125  0.625  1.0
  Fe  Fe3  1  0.625  0.625  0.625  1.0
  Ni  Ni4  1  0.125  0.625  0.625  1.0
  Ni  Ni5  1  0.625  0.625  0.125  1.0
  O  O6  1  0.383  0.376  0.383  1.0
  O  O7  1  0.386  0.377  0.859  1.0
  O  O8  1  0.383  0.857  0.383  1.0
  O  O9  1  0.859  0.377  0.386  1.0
  O  O10  1  0.391  0.873  0.864  1.0
  O  O11  1  0.867  0.393  0.867  1.0
  O  O12  1  0.864  0.873  0.391  1.0
  O  O13  1  0.867  0.874  0.867  1.0
[/CIF]
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