The crystal structure described by CdAl2Se4 is Spinel structured and crystallizes in the cubic Fd-3m space group. Cd(1) is bonded to four equivalent Se(1) atoms to form CdSe4 tetrahedra that share corners with twelve equivalent Al(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 59°. Al(1) is bonded to six equivalent Se(1) atoms to form AlSe6 octahedra that share corners with six equivalent Cd(1)Se4 tetrahedra and edges with six equivalent Al(1)Se6 octahedra. Se(1) is bonded to one Cd(1) and three equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing SeAl3Cd trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2CdSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.668
_cell_length_b   7.668
_cell_length_c   7.668
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   318.824
_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  0.500  0.000  0.500  1.0
  Al  Al1  1  0.000  0.500  0.500  1.0
  Al  Al2  1  0.500  0.500  0.500  1.0
  Al  Al3  1  0.500  0.500  0.000  1.0
  Cd  Cd4  1  0.875  0.875  0.875  1.0
  Cd  Cd5  1  0.125  0.125  0.125  1.0
  Se  Se6  1  0.264  0.264  0.709  1.0
  Se  Se7  1  0.736  0.736  0.736  1.0
  Se  Se8  1  0.264  0.264  0.264  1.0
  Se  Se9  1  0.736  0.736  0.291  1.0
  Se  Se10  1  0.291  0.736  0.736  1.0
  Se  Se11  1  0.736  0.291  0.736  1.0
  Se  Se12  1  0.709  0.264  0.264  1.0
  Se  Se13  1  0.264  0.709  0.264  1.0
[/CIF]
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The crystal structure described by CdAl2Se4 is Spinel structured and crystallizes in the cubic Fd-3m space group. Cd(1) is bonded to four equivalent Se(1) atoms to form CdSe4 tetrahedra that share corners with twelve equivalent Al(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 59°. Al(1) is bonded to six equivalent Se(1) atoms to form AlSe6 octahedra that share corners with six equivalent Cd(1)Se4 tetrahedra and edges with six equivalent Al(1)Se6 octahedra. Se(1) is bonded to one Cd(1) and three equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing SeAl3Cd trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2CdSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.668
_cell_length_b   7.668
_cell_length_c   7.668
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   318.824
_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  0.500  0.000  0.500  1.0
  Al  Al1  1  0.000  0.500  0.500  1.0
  Al  Al2  1  0.500  0.500  0.500  1.0
  Al  Al3  1  0.500  0.500  0.000  1.0
  Cd  Cd4  1  0.875  0.875  0.875  1.0
  Cd  Cd5  1  0.125  0.125  0.125  1.0
  Se  Se6  1  0.264  0.264  0.709  1.0
  Se  Se7  1  0.736  0.736  0.736  1.0
  Se  Se8  1  0.264  0.264  0.264  1.0
  Se  Se9  1  0.736  0.736  0.291  1.0
  Se  Se10  1  0.291  0.736  0.736  1.0
  Se  Se11  1  0.736  0.291  0.736  1.0
  Se  Se12  1  0.709  0.264  0.264  1.0
  Se  Se13  1  0.264  0.709  0.264  1.0
[/CIF]
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