The compound described by CdAl2Se4 crystallizes in the tetragonal I-4 space group. Cd(1) is bonded to four equivalent Se(1) atoms to form CdSe4 tetrahedra that share corners with four equivalent Al(1)Se4 tetrahedra and corners with four equivalent Al(2)Se4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with four equivalent Cd(1)Se4 tetrahedra and corners with four equivalent Al(2)Se4 tetrahedra. In the second Al site, Al(2) is bonded to four equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with four equivalent Cd(1)Se4 tetrahedra and corners with four equivalent Al(1)Se4 tetrahedra. Se(1) is bonded in a trigonal non-coplanar geometry to one Cd(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_Al2CdSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.805
_cell_length_b   5.805
_cell_length_c   6.789
_cell_angle_alpha   115.310
_cell_angle_beta   115.310
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   182.217
_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
  Al  Al0  1  0.250  0.750  0.500  1.0
  Al  Al1  1  0.500  0.500  0.000  1.0
  Cd  Cd2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.867  0.867  0.273  1.0
  Se  Se4  1  0.406  0.406  0.273  1.0
  Se  Se5  1  0.133  0.594  0.727  1.0
  Se  Se6  1  0.594  0.133  0.727  1.0
[/CIF]
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The compound described by CdAl2Se4 crystallizes in the tetragonal I-4 space group. Cd(1) is bonded to four equivalent Se(1) atoms to form CdSe4 tetrahedra that share corners with four equivalent Al(1)Se4 tetrahedra and corners with four equivalent Al(2)Se4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with four equivalent Cd(1)Se4 tetrahedra and corners with four equivalent Al(2)Se4 tetrahedra. In the second Al site, Al(2) is bonded to four equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with four equivalent Cd(1)Se4 tetrahedra and corners with four equivalent Al(1)Se4 tetrahedra. Se(1) is bonded in a trigonal non-coplanar geometry to one Cd(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_Al2CdSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.805
_cell_length_b   5.805
_cell_length_c   6.789
_cell_angle_alpha   115.310
_cell_angle_beta   115.310
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   182.217
_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
  Al  Al0  1  0.250  0.750  0.500  1.0
  Al  Al1  1  0.500  0.500  0.000  1.0
  Cd  Cd2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.867  0.867  0.273  1.0
  Se  Se4  1  0.406  0.406  0.273  1.0
  Se  Se5  1  0.133  0.594  0.727  1.0
  Se  Se6  1  0.594  0.133  0.727  1.0
[/CIF]
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