The crystal 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 6-coordinate geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. Se(1) is bonded in a distorted square pyramidal geometry to one O(1) and 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 two equivalent Na(1) and one Se(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Se(1), and one O(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.185
_cell_length_b   6.185
_cell_length_c   7.919
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.990
_symmetry_Int_Tables_number   1
_cell_volume   264.959
_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  0.647  0.353  0.750  1.0
  Na  Na3  1  0.353  0.647  0.250  1.0
  Se  Se4  1  0.223  0.777  0.750  1.0
  Se  Se5  1  0.777  0.223  0.250  1.0
  O  O6  1  0.934  0.066  0.250  1.0
  O  O7  1  0.066  0.934  0.750  1.0
  O  O8  1  0.967  0.575  0.945  1.0
  O  O9  1  0.575  0.967  0.055  1.0
  O  O10  1  0.967  0.575  0.555  1.0
  O  O11  1  0.575  0.967  0.445  1.0
  O  O12  1  0.033  0.425  0.055  1.0
  O  O13  1  0.425  0.033  0.945  1.0
  O  O14  1  0.033  0.425  0.445  1.0
  O  O15  1  0.425  0.033  0.555  1.0
[/CIF]
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The crystal 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 6-coordinate geometry to two equivalent O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. Se(1) is bonded in a distorted square pyramidal geometry to one O(1) and 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 two equivalent Na(1) and one Se(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Se(1), and one O(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.185
_cell_length_b   6.185
_cell_length_c   7.919
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.990
_symmetry_Int_Tables_number   1
_cell_volume   264.959
_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  0.647  0.353  0.750  1.0
  Na  Na3  1  0.353  0.647  0.250  1.0
  Se  Se4  1  0.223  0.777  0.750  1.0
  Se  Se5  1  0.777  0.223  0.250  1.0
  O  O6  1  0.934  0.066  0.250  1.0
  O  O7  1  0.066  0.934  0.750  1.0
  O  O8  1  0.967  0.575  0.945  1.0
  O  O9  1  0.575  0.967  0.055  1.0
  O  O10  1  0.967  0.575  0.555  1.0
  O  O11  1  0.575  0.967  0.445  1.0
  O  O12  1  0.033  0.425  0.055  1.0
  O  O13  1  0.425  0.033  0.945  1.0
  O  O14  1  0.033  0.425  0.445  1.0
  O  O15  1  0.425  0.033  0.555  1.0
[/CIF]
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