The material described by ZnAl2Se4 crystallizes in the monoclinic Pm space group. Zn(1) is bonded to one Se(1), one Se(4), and two equivalent Se(3) atoms to form ZnSe4 tetrahedra that share corners with two equivalent Zn(1)Se4 tetrahedra, 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 one Se(2), one Se(3), and two equivalent Se(4) atoms to form AlSe4 tetrahedra that share corners with two equivalent Al(1)Se4 tetrahedra, corners with two equivalent Al(2)Se4 tetrahedra, and corners with four equivalent Zn(1)Se4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with two equivalent Al(1)Se4 tetrahedra, corners with two equivalent Al(2)Se4 tetrahedra, and corners with four equivalent Zn(1)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one Zn(1) and two equivalent Al(2) atoms. In the second Se site, Se(2) is bonded in a water-like geometry to one Al(1) and one Al(2) atom. In the third Se site, Se(3) is bonded to two equivalent Zn(1), one Al(1), and one Al(2) atom to form corner-sharing SeAl2Zn2 tetrahedra. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Zn(1) and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2ZnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.870
_cell_length_b   6.517
_cell_length_c   6.987
_cell_angle_alpha   89.669
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   176.220
_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  0.500  0.521  0.170  1.0
  Al  Al1  1  0.500  0.972  0.849  1.0
  Zn  Zn2  1  0.000  0.511  0.656  1.0
  Se  Se3  1  0.000  0.890  0.650  1.0
  Se  Se4  1  0.500  0.879  0.170  1.0
  Se  Se5  1  0.500  0.363  0.843  1.0
  Se  Se6  1  0.000  0.363  0.329  1.0
[/CIF]
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The material described by ZnAl2Se4 crystallizes in the monoclinic Pm space group. Zn(1) is bonded to one Se(1), one Se(4), and two equivalent Se(3) atoms to form ZnSe4 tetrahedra that share corners with two equivalent Zn(1)Se4 tetrahedra, 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 one Se(2), one Se(3), and two equivalent Se(4) atoms to form AlSe4 tetrahedra that share corners with two equivalent Al(1)Se4 tetrahedra, corners with two equivalent Al(2)Se4 tetrahedra, and corners with four equivalent Zn(1)Se4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form AlSe4 tetrahedra that share corners with two equivalent Al(1)Se4 tetrahedra, corners with two equivalent Al(2)Se4 tetrahedra, and corners with four equivalent Zn(1)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a trigonal non-coplanar geometry to one Zn(1) and two equivalent Al(2) atoms. In the second Se site, Se(2) is bonded in a water-like geometry to one Al(1) and one Al(2) atom. In the third Se site, Se(3) is bonded to two equivalent Zn(1), one Al(1), and one Al(2) atom to form corner-sharing SeAl2Zn2 tetrahedra. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to one Zn(1) and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al2ZnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.870
_cell_length_b   6.517
_cell_length_c   6.987
_cell_angle_alpha   89.669
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   176.220
_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  0.500  0.521  0.170  1.0
  Al  Al1  1  0.500  0.972  0.849  1.0
  Zn  Zn2  1  0.000  0.511  0.656  1.0
  Se  Se3  1  0.000  0.890  0.650  1.0
  Se  Se4  1  0.500  0.879  0.170  1.0
  Se  Se5  1  0.500  0.363  0.843  1.0
  Se  Se6  1  0.000  0.363  0.329  1.0
[/CIF]
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