The structure described by Na2SeO5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted square pyramidal geometry to one O(1) and four equivalent O(2) atoms. Se(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Na(2) and two equivalent Na(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Na2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.706
_cell_length_b   6.097
_cell_length_c   9.474
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   123.359
_symmetry_Int_Tables_number   1
_cell_volume   323.533
_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  0.500  1.0
  Na  Na1  1  0.000  0.000  0.000  1.0
  Na  Na2  1  0.669  0.338  0.750  1.0
  Na  Na3  1  0.331  0.662  0.250  1.0
  Se  Se4  1  0.218  0.435  0.750  1.0
  Se  Se5  1  0.782  0.565  0.250  1.0
  O  O6  1  0.085  0.170  0.250  1.0
  O  O7  1  0.915  0.830  0.750  1.0
  O  O8  1  0.962  0.305  0.866  1.0
  O  O9  1  0.656  0.695  0.134  1.0
  O  O10  1  0.962  0.305  0.634  1.0
  O  O11  1  0.656  0.695  0.366  1.0
  O  O12  1  0.038  0.695  0.134  1.0
  O  O13  1  0.344  0.305  0.866  1.0
  O  O14  1  0.038  0.695  0.366  1.0
  O  O15  1  0.344  0.305  0.634  1.0
[/CIF]
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The structure described by Na2SeO5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted square pyramidal geometry to one O(1) and four equivalent O(2) atoms. Se(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Na(2) and two equivalent Na(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Na2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.706
_cell_length_b   6.097
_cell_length_c   9.474
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   123.359
_symmetry_Int_Tables_number   1
_cell_volume   323.533
_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  0.500  1.0
  Na  Na1  1  0.000  0.000  0.000  1.0
  Na  Na2  1  0.669  0.338  0.750  1.0
  Na  Na3  1  0.331  0.662  0.250  1.0
  Se  Se4  1  0.218  0.435  0.750  1.0
  Se  Se5  1  0.782  0.565  0.250  1.0
  O  O6  1  0.085  0.170  0.250  1.0
  O  O7  1  0.915  0.830  0.750  1.0
  O  O8  1  0.962  0.305  0.866  1.0
  O  O9  1  0.656  0.695  0.134  1.0
  O  O10  1  0.962  0.305  0.634  1.0
  O  O11  1  0.656  0.695  0.366  1.0
  O  O12  1  0.038  0.695  0.134  1.0
  O  O13  1  0.344  0.305  0.866  1.0
  O  O14  1  0.038  0.695  0.366  1.0
  O  O15  1  0.344  0.305  0.634  1.0
[/CIF]
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