The material structure described by Na3AlSe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent Se(2) and two equivalent Se(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to two equivalent Se(2) and two equivalent Se(3) atoms. Al(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted edge-sharing AlSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Al(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Al(1) atom. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Al(1) atom. is represented by the CIF file [CIF]
data_Na3AlSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.195
_cell_length_b   7.462
_cell_length_c   15.063
_cell_angle_alpha   60.616
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   704.762
_cell_formula_units_Z   4
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
  Na  Na0  1  0.027  0.940  0.286  1.0
  Na  Na1  1  0.527  0.060  0.214  1.0
  Na  Na2  1  0.973  0.060  0.714  1.0
  Na  Na3  1  0.473  0.940  0.786  1.0
  Na  Na4  1  0.996  0.729  0.110  1.0
  Na  Na5  1  0.496  0.271  0.390  1.0
  Na  Na6  1  0.004  0.271  0.890  1.0
  Na  Na7  1  0.504  0.729  0.610  1.0
  Na  Na8  1  0.996  0.308  0.398  1.0
  Na  Na9  1  0.496  0.692  0.102  1.0
  Na  Na10  1  0.004  0.692  0.602  1.0
  Na  Na11  1  0.504  0.308  0.898  1.0
  Al  Al12  1  0.641  0.662  0.420  1.0
  Al  Al13  1  0.141  0.338  0.080  1.0
  Al  Al14  1  0.359  0.338  0.580  1.0
  Al  Al15  1  0.859  0.662  0.920  1.0
  Se  Se16  1  0.802  0.345  0.073  1.0
  Se  Se17  1  0.302  0.655  0.427  1.0
  Se  Se18  1  0.198  0.655  0.927  1.0
  Se  Se19  1  0.698  0.345  0.573  1.0
  Se  Se20  1  0.241  0.345  0.227  1.0
  Se  Se21  1  0.741  0.655  0.273  1.0
  Se  Se22  1  0.759  0.655  0.773  1.0
  Se  Se23  1  0.259  0.345  0.727  1.0
  Se  Se24  1  0.756  0.949  0.427  1.0
  Se  Se25  1  0.256  0.051  0.073  1.0
  Se  Se26  1  0.244  0.051  0.573  1.0
  Se  Se27  1  0.744  0.949  0.927  1.0
[/CIF]
.
The material structure described by Na3AlSe3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent Se(2) and two equivalent Se(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to two equivalent Se(2) and two equivalent Se(3) atoms. Al(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted edge-sharing AlSe4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Al(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Al(1) atom. In the third Se site, Se(3) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Al(1) atom. is represented by the CIF file [CIF]
data_Na3AlSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.195
_cell_length_b   7.462
_cell_length_c   15.063
_cell_angle_alpha   60.616
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   704.762
_cell_formula_units_Z   4
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
  Na  Na0  1  0.027  0.940  0.286  1.0
  Na  Na1  1  0.527  0.060  0.214  1.0
  Na  Na2  1  0.973  0.060  0.714  1.0
  Na  Na3  1  0.473  0.940  0.786  1.0
  Na  Na4  1  0.996  0.729  0.110  1.0
  Na  Na5  1  0.496  0.271  0.390  1.0
  Na  Na6  1  0.004  0.271  0.890  1.0
  Na  Na7  1  0.504  0.729  0.610  1.0
  Na  Na8  1  0.996  0.308  0.398  1.0
  Na  Na9  1  0.496  0.692  0.102  1.0
  Na  Na10  1  0.004  0.692  0.602  1.0
  Na  Na11  1  0.504  0.308  0.898  1.0
  Al  Al12  1  0.641  0.662  0.420  1.0
  Al  Al13  1  0.141  0.338  0.080  1.0
  Al  Al14  1  0.359  0.338  0.580  1.0
  Al  Al15  1  0.859  0.662  0.920  1.0
  Se  Se16  1  0.802  0.345  0.073  1.0
  Se  Se17  1  0.302  0.655  0.427  1.0
  Se  Se18  1  0.198  0.655  0.927  1.0
  Se  Se19  1  0.698  0.345  0.573  1.0
  Se  Se20  1  0.241  0.345  0.227  1.0
  Se  Se21  1  0.741  0.655  0.273  1.0
  Se  Se22  1  0.759  0.655  0.773  1.0
  Se  Se23  1  0.259  0.345  0.727  1.0
  Se  Se24  1  0.756  0.949  0.427  1.0
  Se  Se25  1  0.256  0.051  0.073  1.0
  Se  Se26  1  0.244  0.051  0.573  1.0
  Se  Se27  1  0.744  0.949  0.927  1.0
[/CIF]
.