The structure described by Cr2O3 is Corundum-like structured and crystallizes in the trigonal R-3 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to six equivalent O(1) atoms to form a mixture of edge and corner-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 42°. In the second Cr site, Cr(2) is bonded to six equivalent O(1) atoms to form a mixture of edge, corner, and face-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the third Cr site, Cr(3) is bonded to six equivalent O(1) atoms to form a mixture of corner and face-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles range from 42-53°. O(1) is bonded to one Cr(1), one Cr(3), and two equivalent Cr(2) atoms to form a mixture of edge and corner-sharing OCr4 trigonal pyramids. is represented by the CIF file [CIF]
data_Cr2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.057
_cell_length_b   5.528
_cell_length_c   5.057
_cell_angle_alpha   117.224
_cell_angle_beta   60.000
_cell_angle_gamma   117.224
_symmetry_Int_Tables_number   1
_cell_volume   103.963
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.313  0.938  0.313  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.687  0.062  0.687  1.0
  O  O4  1  0.285  0.781  0.610  1.0
  O  O5  1  0.390  0.219  0.114  1.0
  O  O6  1  0.114  0.219  0.715  1.0
  O  O7  1  0.886  0.781  0.285  1.0
  O  O8  1  0.610  0.781  0.886  1.0
  O  O9  1  0.715  0.219  0.390  1.0
[/CIF]
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The structure described by Cr2O3 is Corundum-like structured and crystallizes in the trigonal R-3 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to six equivalent O(1) atoms to form a mixture of edge and corner-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 42°. In the second Cr site, Cr(2) is bonded to six equivalent O(1) atoms to form a mixture of edge, corner, and face-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the third Cr site, Cr(3) is bonded to six equivalent O(1) atoms to form a mixture of corner and face-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles range from 42-53°. O(1) is bonded to one Cr(1), one Cr(3), and two equivalent Cr(2) atoms to form a mixture of edge and corner-sharing OCr4 trigonal pyramids. is represented by the CIF file [CIF]
data_Cr2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.057
_cell_length_b   5.528
_cell_length_c   5.057
_cell_angle_alpha   117.224
_cell_angle_beta   60.000
_cell_angle_gamma   117.224
_symmetry_Int_Tables_number   1
_cell_volume   103.963
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Cr  Cr1  1  0.313  0.938  0.313  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.687  0.062  0.687  1.0
  O  O4  1  0.285  0.781  0.610  1.0
  O  O5  1  0.390  0.219  0.114  1.0
  O  O6  1  0.114  0.219  0.715  1.0
  O  O7  1  0.886  0.781  0.285  1.0
  O  O8  1  0.610  0.781  0.886  1.0
  O  O9  1  0.715  0.219  0.390  1.0
[/CIF]
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