The material structure described by Cr2AlO4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Al(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Al(1) atom. In the second O site, O(2) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.437
_cell_length_b   6.437
_cell_length_c   5.345
_cell_angle_alpha   65.673
_cell_angle_beta   65.673
_cell_angle_gamma   108.288
_symmetry_Int_Tables_number   1
_cell_volume   149.509
_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  0.121  0.879  0.250  1.0
  Al  Al1  1  0.879  0.121  0.750  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.000  1.0
  Cr  Cr4  1  0.500  0.000  0.500  1.0
  Cr  Cr5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.910  0.722  0.728  1.0
  O  O7  1  0.278  0.090  0.772  1.0
  O  O8  1  0.090  0.278  0.272  1.0
  O  O9  1  0.722  0.910  0.228  1.0
  O  O10  1  0.137  0.446  0.645  1.0
  O  O11  1  0.554  0.863  0.855  1.0
  O  O12  1  0.446  0.137  0.145  1.0
  O  O13  1  0.863  0.554  0.355  1.0
[/CIF]
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The material structure described by Cr2AlO4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Al(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Al(1) atom. In the second O site, O(2) is bonded in a trigonal non-coplanar geometry to one Cr(1), one Cr(2), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.437
_cell_length_b   6.437
_cell_length_c   5.345
_cell_angle_alpha   65.673
_cell_angle_beta   65.673
_cell_angle_gamma   108.288
_symmetry_Int_Tables_number   1
_cell_volume   149.509
_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  0.121  0.879  0.250  1.0
  Al  Al1  1  0.879  0.121  0.750  1.0
  Cr  Cr2  1  0.500  0.500  0.500  1.0
  Cr  Cr3  1  0.500  0.500  0.000  1.0
  Cr  Cr4  1  0.500  0.000  0.500  1.0
  Cr  Cr5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.910  0.722  0.728  1.0
  O  O7  1  0.278  0.090  0.772  1.0
  O  O8  1  0.090  0.278  0.272  1.0
  O  O9  1  0.722  0.910  0.228  1.0
  O  O10  1  0.137  0.446  0.645  1.0
  O  O11  1  0.554  0.863  0.855  1.0
  O  O12  1  0.446  0.137  0.145  1.0
  O  O13  1  0.863  0.554  0.355  1.0
[/CIF]
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