The material structure described by Na2ZnSe2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(2) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to four equivalent Se(2) atoms. Zn(1) is bonded to one Se(2) and three equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing ZnSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Na(1) and three equivalent Zn(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Na(1), four equivalent Na(2), and one Zn(1) atom to form a mixture of distorted edge and corner-sharing SeNa6Zn pentagonal bipyramids. is represented by the CIF card [CIF]
data_Na2ZnSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.352
_cell_length_b   7.130
_cell_length_c   9.124
_cell_angle_alpha   86.509
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   477.316
_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  0.179  0.953  0.676  1.0
  Na  Na1  1  0.679  0.547  0.324  1.0
  Na  Na2  1  0.821  0.047  0.324  1.0
  Na  Na3  1  0.321  0.453  0.676  1.0
  Na  Na4  1  0.265  0.988  0.056  1.0
  Na  Na5  1  0.765  0.512  0.944  1.0
  Na  Na6  1  0.735  0.012  0.944  1.0
  Na  Na7  1  0.235  0.488  0.056  1.0
  Zn  Zn8  1  0.091  0.655  0.372  1.0
  Zn  Zn9  1  0.591  0.845  0.628  1.0
  Zn  Zn10  1  0.909  0.345  0.628  1.0
  Zn  Zn11  1  0.409  0.155  0.372  1.0
  Se  Se12  1  0.609  0.198  0.594  1.0
  Se  Se13  1  0.109  0.302  0.406  1.0
  Se  Se14  1  0.391  0.802  0.406  1.0
  Se  Se15  1  0.891  0.698  0.594  1.0
  Se  Se16  1  0.545  0.255  0.143  1.0
  Se  Se17  1  0.045  0.245  0.857  1.0
  Se  Se18  1  0.455  0.745  0.857  1.0
  Se  Se19  1  0.955  0.755  0.143  1.0
[/CIF]
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The material structure described by Na2ZnSe2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one Se(1) and two equivalent Se(2) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to four equivalent Se(2) atoms. Zn(1) is bonded to one Se(2) and three equivalent Se(1) atoms to form a mixture of distorted edge and corner-sharing ZnSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Na(1) and three equivalent Zn(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Na(1), four equivalent Na(2), and one Zn(1) atom to form a mixture of distorted edge and corner-sharing SeNa6Zn pentagonal bipyramids. is represented by the CIF card [CIF]
data_Na2ZnSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.352
_cell_length_b   7.130
_cell_length_c   9.124
_cell_angle_alpha   86.509
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   477.316
_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  0.179  0.953  0.676  1.0
  Na  Na1  1  0.679  0.547  0.324  1.0
  Na  Na2  1  0.821  0.047  0.324  1.0
  Na  Na3  1  0.321  0.453  0.676  1.0
  Na  Na4  1  0.265  0.988  0.056  1.0
  Na  Na5  1  0.765  0.512  0.944  1.0
  Na  Na6  1  0.735  0.012  0.944  1.0
  Na  Na7  1  0.235  0.488  0.056  1.0
  Zn  Zn8  1  0.091  0.655  0.372  1.0
  Zn  Zn9  1  0.591  0.845  0.628  1.0
  Zn  Zn10  1  0.909  0.345  0.628  1.0
  Zn  Zn11  1  0.409  0.155  0.372  1.0
  Se  Se12  1  0.609  0.198  0.594  1.0
  Se  Se13  1  0.109  0.302  0.406  1.0
  Se  Se14  1  0.391  0.802  0.406  1.0
  Se  Se15  1  0.891  0.698  0.594  1.0
  Se  Se16  1  0.545  0.255  0.143  1.0
  Se  Se17  1  0.045  0.245  0.857  1.0
  Se  Se18  1  0.455  0.745  0.857  1.0
  Se  Se19  1  0.955  0.755  0.143  1.0
[/CIF]
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