The compound described by KCr2AlO10 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(3) atoms. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CrO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 34°. Al(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form AlO6 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one Cr(1), and one Al(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Al(1) atom. is represented by the CIF file [CIF]
data_KAlCr2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.159
_cell_length_b   6.159
_cell_length_c   7.896
_cell_angle_alpha   73.199
_cell_angle_beta   73.199
_cell_angle_gamma   52.745
_symmetry_Int_Tables_number   1
_cell_volume   225.620
_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
  K  K0  1  0.000  0.000  0.500  1.0
  Al  Al1  1  0.000  0.000  0.000  1.0
  Cr  Cr2  1  0.383  0.383  0.273  1.0
  Cr  Cr3  1  0.617  0.617  0.727  1.0
  O  O4  1  0.209  0.729  0.181  1.0
  O  O5  1  0.729  0.209  0.181  1.0
  O  O6  1  0.791  0.271  0.819  1.0
  O  O7  1  0.271  0.791  0.819  1.0
  O  O8  1  0.246  0.246  0.241  1.0
  O  O9  1  0.754  0.754  0.759  1.0
  O  O10  1  0.363  0.363  0.485  1.0
  O  O11  1  0.637  0.637  0.515  1.0
  O  O12  1  0.178  0.178  0.916  1.0
  O  O13  1  0.822  0.822  0.084  1.0
[/CIF]
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The compound described by KCr2AlO10 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), four equivalent O(1), and four equivalent O(3) atoms. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CrO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 34°. Al(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form AlO6 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one Cr(1), and one Al(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one K(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Al(1) atom. is represented by the CIF file [CIF]
data_KAlCr2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.159
_cell_length_b   6.159
_cell_length_c   7.896
_cell_angle_alpha   73.199
_cell_angle_beta   73.199
_cell_angle_gamma   52.745
_symmetry_Int_Tables_number   1
_cell_volume   225.620
_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
  K  K0  1  0.000  0.000  0.500  1.0
  Al  Al1  1  0.000  0.000  0.000  1.0
  Cr  Cr2  1  0.383  0.383  0.273  1.0
  Cr  Cr3  1  0.617  0.617  0.727  1.0
  O  O4  1  0.209  0.729  0.181  1.0
  O  O5  1  0.729  0.209  0.181  1.0
  O  O6  1  0.791  0.271  0.819  1.0
  O  O7  1  0.271  0.791  0.819  1.0
  O  O8  1  0.246  0.246  0.241  1.0
  O  O9  1  0.754  0.754  0.759  1.0
  O  O10  1  0.363  0.363  0.485  1.0
  O  O11  1  0.637  0.637  0.515  1.0
  O  O12  1  0.178  0.178  0.916  1.0
  O  O13  1  0.822  0.822  0.084  1.0
[/CIF]
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