The structure described by Na2SO4 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. In the second Na site, Na(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form edge-sharing NaO12 cuboctahedra. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one S(1) and three equivalent O(1) atoms. S(1) is bonded in a distorted single-bond geometry to one Na(3) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one Na(3) atom. In the second O site, O(2) is bonded in a single-bond geometry to three equivalent Na(2) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2SO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.975
_cell_length_b   4.975
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   179.109
_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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Na  Na2  1  0.333  0.667  0.049  1.0
  Na  Na3  1  0.667  0.333  0.951  1.0
  S  S4  1  0.667  0.333  0.280  1.0
  S  S5  1  0.333  0.667  0.720  1.0
  O  O6  1  0.847  0.153  0.770  1.0
  O  O7  1  0.847  0.695  0.770  1.0
  O  O8  1  0.305  0.153  0.770  1.0
  O  O9  1  0.695  0.847  0.230  1.0
  O  O10  1  0.153  0.305  0.230  1.0
  O  O11  1  0.153  0.847  0.230  1.0
  O  O12  1  0.667  0.333  0.453  1.0
  O  O13  1  0.333  0.667  0.547  1.0
[/CIF]
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The structure described by Na2SO4 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. In the second Na site, Na(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form edge-sharing NaO12 cuboctahedra. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one S(1) and three equivalent O(1) atoms. S(1) is bonded in a distorted single-bond geometry to one Na(3) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one Na(3) atom. In the second O site, O(2) is bonded in a single-bond geometry to three equivalent Na(2) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2SO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.975
_cell_length_b   4.975
_cell_length_c   8.356
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   179.109
_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
  Na  Na0  1  0.000  0.000  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Na  Na2  1  0.333  0.667  0.049  1.0
  Na  Na3  1  0.667  0.333  0.951  1.0
  S  S4  1  0.667  0.333  0.280  1.0
  S  S5  1  0.333  0.667  0.720  1.0
  O  O6  1  0.847  0.153  0.770  1.0
  O  O7  1  0.847  0.695  0.770  1.0
  O  O8  1  0.305  0.153  0.770  1.0
  O  O9  1  0.695  0.847  0.230  1.0
  O  O10  1  0.153  0.305  0.230  1.0
  O  O11  1  0.153  0.847  0.230  1.0
  O  O12  1  0.667  0.333  0.453  1.0
  O  O13  1  0.333  0.667  0.547  1.0
[/CIF]
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