The material structure described by Al2PbSe4 crystallizes in the monoclinic Pm space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(2), and two equivalent Se(6) atoms to form a mixture of corner and edge-sharing AlSe4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), and two equivalent Se(6) atoms to form a mixture of corner and edge-sharing AlSe4 tetrahedra. In the third Al site, Al(3) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form edge-sharing AlSe4 tetrahedra. In the fourth Al site, Al(4) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form edge-sharing AlSe4 tetrahedra. Pb(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted bent 120 degrees geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a distorted bent 120 degrees geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the fifth Se site, Se(5) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the sixth Se site, Se(6) is bonded in a 2-coordinate geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. is represented by the CIF card [CIF]
data_Al2PbSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.259
_cell_length_b   6.302
_cell_length_c   10.921
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.638
_symmetry_Int_Tables_number   1
_cell_volume   374.390
_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  0.221  0.950  0.500  1.0
  Al  Al1  1  0.772  0.231  0.500  1.0
  Al  Al2  1  0.764  0.246  0.000  1.0
  Al  Al3  1  0.239  0.763  0.000  1.0
  Pb  Pb4  1  0.502  0.495  0.250  1.0
  Pb  Pb5  1  0.502  0.495  0.750  1.0
  Se  Se6  1  0.810  0.631  0.500  1.0
  Se  Se7  1  0.181  0.312  0.500  1.0
  Se  Se8  1  0.349  0.186  0.000  1.0
  Se  Se9  1  0.653  0.825  0.000  1.0
  Se  Se10  1  0.001  0.505  0.167  1.0
  Se  Se11  1  0.497  0.014  0.333  1.0
  Se  Se12  1  0.001  0.505  0.833  1.0
  Se  Se13  1  0.497  0.014  0.667  1.0
[/CIF]
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The material structure described by Al2PbSe4 crystallizes in the monoclinic Pm space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one Se(1), one Se(2), and two equivalent Se(6) atoms to form a mixture of corner and edge-sharing AlSe4 tetrahedra. In the second Al site, Al(2) is bonded to one Se(1), one Se(2), and two equivalent Se(6) atoms to form a mixture of corner and edge-sharing AlSe4 tetrahedra. In the third Al site, Al(3) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form edge-sharing AlSe4 tetrahedra. In the fourth Al site, Al(4) is bonded to one Se(3), one Se(4), and two equivalent Se(5) atoms to form edge-sharing AlSe4 tetrahedra. Pb(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), two equivalent Se(5), and two equivalent Se(6) atoms. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted bent 120 degrees geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. In the second Se site, Se(2) is bonded in a distorted bent 120 degrees geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the fifth Se site, Se(5) is bonded in a distorted L-shaped geometry to one Al(3), one Al(4), and two equivalent Pb(1) atoms. In the sixth Se site, Se(6) is bonded in a 2-coordinate geometry to one Al(1), one Al(2), and two equivalent Pb(1) atoms. is represented by the CIF card [CIF]
data_Al2PbSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.259
_cell_length_b   6.302
_cell_length_c   10.921
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.638
_symmetry_Int_Tables_number   1
_cell_volume   374.390
_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  0.221  0.950  0.500  1.0
  Al  Al1  1  0.772  0.231  0.500  1.0
  Al  Al2  1  0.764  0.246  0.000  1.0
  Al  Al3  1  0.239  0.763  0.000  1.0
  Pb  Pb4  1  0.502  0.495  0.250  1.0
  Pb  Pb5  1  0.502  0.495  0.750  1.0
  Se  Se6  1  0.810  0.631  0.500  1.0
  Se  Se7  1  0.181  0.312  0.500  1.0
  Se  Se8  1  0.349  0.186  0.000  1.0
  Se  Se9  1  0.653  0.825  0.000  1.0
  Se  Se10  1  0.001  0.505  0.167  1.0
  Se  Se11  1  0.497  0.014  0.333  1.0
  Se  Se12  1  0.001  0.505  0.833  1.0
  Se  Se13  1  0.497  0.014  0.667  1.0
[/CIF]
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