The compound described by MgCr2(FeO3)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(1)O6 octahedra, edges with six equivalent Cr(1)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. Cr(1) is bonded to six equivalent O(1) atoms to form CrO6 octahedra that share corners with nine equivalent Fe(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Cr(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Cr(1)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. O(1) is bonded to one Mg(1), two equivalent Cr(1), and two equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing OMgCr2Fe2 trigonal bipyramids. is represented by the CIF file [CIF]
data_MgCr2(FeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.176
_cell_length_b   5.176
_cell_length_c   5.865
_cell_angle_alpha   63.797
_cell_angle_beta   63.804
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   117.058
_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  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.345  0.345  0.966  1.0
  Cr  Cr2  1  0.655  0.655  0.034  1.0
  Fe  Fe3  1  0.169  0.169  0.494  1.0
  Fe  Fe4  1  0.831  0.831  0.506  1.0
  O  O5  1  0.945  0.252  0.223  1.0
  O  O6  1  0.252  0.580  0.223  1.0
  O  O7  1  0.580  0.945  0.223  1.0
  O  O8  1  0.055  0.748  0.777  1.0
  O  O9  1  0.748  0.420  0.777  1.0
  O  O10  1  0.420  0.055  0.777  1.0
[/CIF]
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The compound described by MgCr2(FeO3)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(1)O6 octahedra, edges with six equivalent Cr(1)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 45°. Cr(1) is bonded to six equivalent O(1) atoms to form CrO6 octahedra that share corners with nine equivalent Fe(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, edges with three equivalent Cr(1)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. Fe(1) is bonded to six equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with nine equivalent Cr(1)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-54°. O(1) is bonded to one Mg(1), two equivalent Cr(1), and two equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing OMgCr2Fe2 trigonal bipyramids. is represented by the CIF file [CIF]
data_MgCr2(FeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.176
_cell_length_b   5.176
_cell_length_c   5.865
_cell_angle_alpha   63.797
_cell_angle_beta   63.804
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   117.058
_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  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.345  0.345  0.966  1.0
  Cr  Cr2  1  0.655  0.655  0.034  1.0
  Fe  Fe3  1  0.169  0.169  0.494  1.0
  Fe  Fe4  1  0.831  0.831  0.506  1.0
  O  O5  1  0.945  0.252  0.223  1.0
  O  O6  1  0.252  0.580  0.223  1.0
  O  O7  1  0.580  0.945  0.223  1.0
  O  O8  1  0.055  0.748  0.777  1.0
  O  O9  1  0.748  0.420  0.777  1.0
  O  O10  1  0.420  0.055  0.777  1.0
[/CIF]
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