The compound described by Mg(Fe2O3)2 crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with six equivalent Fe(1)O6 octahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with nine equivalent Fe(2)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra, and  a faceface with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Fe(1)O6 octahedra, edges with three equivalent Fe(2)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. O(1) is bonded to one Mg(1), two equivalent Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted corner and edge-sharing OMgFe4 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg(Fe2O3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.218
_cell_length_b   5.858
_cell_length_c   5.218
_cell_angle_alpha   63.601
_cell_angle_beta   119.992
_cell_angle_gamma   116.444
_symmetry_Int_Tables_number   1
_cell_volume   118.505
_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  1.000  0.000  0.000  1.0
  Fe  Fe1  1  0.355  0.064  0.645  1.0
  Fe  Fe2  1  0.172  0.517  0.828  1.0
  Fe  Fe3  1  0.645  0.936  0.355  1.0
  Fe  Fe4  1  0.828  0.483  0.172  1.0
  O  O5  1  0.584  0.773  0.059  1.0
  O  O6  1  0.248  0.773  0.415  1.0
  O  O7  1  0.059  0.227  0.248  1.0
  O  O8  1  0.752  0.227  0.585  1.0
  O  O9  1  0.416  0.227  0.941  1.0
  O  O10  1  0.941  0.773  0.752  1.0
[/CIF]
.
The compound described by Mg(Fe2O3)2 crystallizes in the trigonal R-3 space group. Mg(1) is bonded to six equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with six equivalent Fe(1)O6 octahedra, and faces with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with nine equivalent Fe(2)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra, and  a faceface with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Fe(1)O6 octahedra, edges with three equivalent Fe(2)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. O(1) is bonded to one Mg(1), two equivalent Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted corner and edge-sharing OMgFe4 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg(Fe2O3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.218
_cell_length_b   5.858
_cell_length_c   5.218
_cell_angle_alpha   63.601
_cell_angle_beta   119.992
_cell_angle_gamma   116.444
_symmetry_Int_Tables_number   1
_cell_volume   118.505
_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  1.000  0.000  0.000  1.0
  Fe  Fe1  1  0.355  0.064  0.645  1.0
  Fe  Fe2  1  0.172  0.517  0.828  1.0
  Fe  Fe3  1  0.645  0.936  0.355  1.0
  Fe  Fe4  1  0.828  0.483  0.172  1.0
  O  O5  1  0.584  0.773  0.059  1.0
  O  O6  1  0.248  0.773  0.415  1.0
  O  O7  1  0.059  0.227  0.248  1.0
  O  O8  1  0.752  0.227  0.585  1.0
  O  O9  1  0.416  0.227  0.941  1.0
  O  O10  1  0.941  0.773  0.752  1.0
[/CIF]
.