The crystal structure described by AlFe2O4 is Spinel structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with six equivalent Fe(1)O6 octahedra. Al(1) is bonded to one O(2) and three equivalent O(1) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra and corners with nine equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Fe(2), two equivalent Fe(1), and one Al(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to three equivalent Fe(1) and one Al(1) atom. is represented by the CIF card [CIF]
data_Al(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.970
_cell_length_b   5.970
_cell_length_c   5.970
_cell_angle_alpha   59.090
_cell_angle_beta   59.090
_cell_angle_gamma   59.090
_symmetry_Int_Tables_number   1
_cell_volume   147.361
_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
  Al  Al0  1  0.627  0.627  0.627  1.0
  Al  Al1  1  0.373  0.373  0.373  1.0
  Fe  Fe2  1  0.500  0.000  0.000  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.753  0.251  0.753  1.0
  O  O7  1  0.247  0.247  0.749  1.0
  O  O8  1  0.749  0.247  0.247  1.0
  O  O9  1  0.251  0.251  0.251  1.0
  O  O10  1  0.753  0.753  0.251  1.0
  O  O11  1  0.247  0.749  0.247  1.0
  O  O12  1  0.251  0.753  0.753  1.0
  O  O13  1  0.749  0.749  0.749  1.0
[/CIF]
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The crystal structure described by AlFe2O4 is Spinel structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with six equivalent Fe(1)O6 octahedra. Al(1) is bonded to one O(2) and three equivalent O(1) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra and corners with nine equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Fe(2), two equivalent Fe(1), and one Al(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to three equivalent Fe(1) and one Al(1) atom. is represented by the CIF card [CIF]
data_Al(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.970
_cell_length_b   5.970
_cell_length_c   5.970
_cell_angle_alpha   59.090
_cell_angle_beta   59.090
_cell_angle_gamma   59.090
_symmetry_Int_Tables_number   1
_cell_volume   147.361
_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
  Al  Al0  1  0.627  0.627  0.627  1.0
  Al  Al1  1  0.373  0.373  0.373  1.0
  Fe  Fe2  1  0.500  0.000  0.000  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.753  0.251  0.753  1.0
  O  O7  1  0.247  0.247  0.749  1.0
  O  O8  1  0.749  0.247  0.247  1.0
  O  O9  1  0.251  0.251  0.251  1.0
  O  O10  1  0.753  0.753  0.251  1.0
  O  O11  1  0.247  0.749  0.247  1.0
  O  O12  1  0.251  0.753  0.753  1.0
  O  O13  1  0.749  0.749  0.749  1.0
[/CIF]
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