The compound described by CrAl2O5 crystallizes in the orthorhombic Cmcm space group. Cr(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and edges with six equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-45°. Al(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, edges with three equivalent Cr(1)O6 octahedra, and edges with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-53°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cr(1) and two equivalent Al(1) atoms to form distorted OAl2Cr2 trigonal pyramids that share corners with two equivalent O(1)Al2Cr2 trigonal pyramids, corners with two equivalent O(3)Al3Cr trigonal pyramids, and edges with four equivalent O(3)Al3Cr trigonal pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Cr(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to one Cr(1) and three equivalent Al(1) atoms to form distorted OAl3Cr trigonal pyramids that share  a cornercorner with one O(1)Al2Cr2 trigonal pyramid, corners with three equivalent O(3)Al3Cr trigonal pyramids, edges with two equivalent O(1)Al2Cr2 trigonal pyramids, and edges with two equivalent O(3)Al3Cr trigonal pyramids. is represented by the CIF file [CIF]
data_Al2CrO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.608
_cell_length_b   5.058
_cell_length_c   9.594
_cell_angle_alpha   89.994
_cell_angle_beta   89.997
_cell_angle_gamma   69.121
_symmetry_Int_Tables_number   1
_cell_volume   163.573
_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  0.860  0.280  0.441  1.0
  Al  Al1  1  0.860  0.280  0.059  1.0
  Al  Al2  1  0.140  0.720  0.941  1.0
  Al  Al3  1  0.140  0.720  0.559  1.0
  Cr  Cr4  1  0.815  0.369  0.750  1.0
  Cr  Cr5  1  0.184  0.631  0.250  1.0
  O  O6  1  0.763  0.474  0.250  1.0
  O  O7  1  0.237  0.526  0.750  1.0
  O  O8  1  0.953  0.094  0.885  1.0
  O  O9  1  0.953  0.095  0.615  1.0
  O  O10  1  0.047  0.905  0.385  1.0
  O  O11  1  0.047  0.905  0.115  1.0
  O  O12  1  0.688  0.623  0.572  1.0
  O  O13  1  0.688  0.623  0.928  1.0
  O  O14  1  0.312  0.377  0.072  1.0
  O  O15  1  0.312  0.377  0.428  1.0
[/CIF]
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The compound described by CrAl2O5 crystallizes in the orthorhombic Cmcm space group. Cr(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Al(1)O6 octahedra, and edges with six equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-45°. Al(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form distorted AlO6 octahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Al(1)O6 octahedra, edges with three equivalent Cr(1)O6 octahedra, and edges with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-53°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cr(1) and two equivalent Al(1) atoms to form distorted OAl2Cr2 trigonal pyramids that share corners with two equivalent O(1)Al2Cr2 trigonal pyramids, corners with two equivalent O(3)Al3Cr trigonal pyramids, and edges with four equivalent O(3)Al3Cr trigonal pyramids. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Cr(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to one Cr(1) and three equivalent Al(1) atoms to form distorted OAl3Cr trigonal pyramids that share  a cornercorner with one O(1)Al2Cr2 trigonal pyramid, corners with three equivalent O(3)Al3Cr trigonal pyramids, edges with two equivalent O(1)Al2Cr2 trigonal pyramids, and edges with two equivalent O(3)Al3Cr trigonal pyramids. is represented by the CIF file [CIF]
data_Al2CrO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.608
_cell_length_b   5.058
_cell_length_c   9.594
_cell_angle_alpha   89.994
_cell_angle_beta   89.997
_cell_angle_gamma   69.121
_symmetry_Int_Tables_number   1
_cell_volume   163.573
_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  0.860  0.280  0.441  1.0
  Al  Al1  1  0.860  0.280  0.059  1.0
  Al  Al2  1  0.140  0.720  0.941  1.0
  Al  Al3  1  0.140  0.720  0.559  1.0
  Cr  Cr4  1  0.815  0.369  0.750  1.0
  Cr  Cr5  1  0.184  0.631  0.250  1.0
  O  O6  1  0.763  0.474  0.250  1.0
  O  O7  1  0.237  0.526  0.750  1.0
  O  O8  1  0.953  0.094  0.885  1.0
  O  O9  1  0.953  0.095  0.615  1.0
  O  O10  1  0.047  0.905  0.385  1.0
  O  O11  1  0.047  0.905  0.115  1.0
  O  O12  1  0.688  0.623  0.572  1.0
  O  O13  1  0.688  0.623  0.928  1.0
  O  O14  1  0.312  0.377  0.072  1.0
  O  O15  1  0.312  0.377  0.428  1.0
[/CIF]
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