The compound described by NaHSeO4 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with six equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 67°. H(1) is bonded in a single-bond geometry to one O(3) and one O(4) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-65°. There are four 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 trigonal planar geometry to two equivalent Na(1) and one Se(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one Se(1) atom. is represented by the CIF file [CIF]
data_NaHSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.987
_cell_length_b   5.361
_cell_length_c   9.545
_cell_angle_alpha   67.881
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   378.593
_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  0.000  0.500  0.704  1.0
  Na  Na1  1  0.500  0.500  0.204  1.0
  Na  Na2  1  1.000  0.500  0.296  1.0
  Na  Na3  1  0.500  0.500  0.796  1.0
  H  H4  1  0.538  0.134  0.632  1.0
  H  H5  1  0.962  0.134  0.132  1.0
  H  H6  1  0.462  0.866  0.368  1.0
  H  H7  1  0.038  0.866  0.868  1.0
  Se  Se8  1  0.275  0.086  0.562  1.0
  Se  Se9  1  0.225  0.086  0.062  1.0
  Se  Se10  1  0.725  0.914  0.438  1.0
  Se  Se11  1  0.775  0.914  0.938  1.0
  O  O12  1  0.108  0.273  0.549  1.0
  O  O13  1  0.392  0.273  0.049  1.0
  O  O14  1  0.892  0.727  0.451  1.0
  O  O15  1  0.608  0.727  0.951  1.0
  O  O16  1  0.254  0.769  0.678  1.0
  O  O17  1  0.246  0.769  0.178  1.0
  O  O18  1  0.746  0.231  0.322  1.0
  O  O19  1  0.754  0.231  0.822  1.0
  O  O20  1  0.343  0.120  0.391  1.0
  O  O21  1  0.157  0.120  0.891  1.0
  O  O22  1  0.657  0.880  0.609  1.0
  O  O23  1  0.843  0.880  0.109  1.0
  O  O24  1  0.432  0.234  0.639  1.0
  O  O25  1  0.068  0.234  0.139  1.0
  O  O26  1  0.568  0.766  0.361  1.0
  O  O27  1  0.932  0.766  0.861  1.0
[/CIF]
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The compound described by NaHSeO4 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with six equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 67°. H(1) is bonded in a single-bond geometry to one O(3) and one O(4) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-65°. There are four 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 trigonal planar geometry to two equivalent Na(1) and one Se(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one H(1), and one Se(1) atom. is represented by the CIF file [CIF]
data_NaHSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.987
_cell_length_b   5.361
_cell_length_c   9.545
_cell_angle_alpha   67.881
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   378.593
_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  0.000  0.500  0.704  1.0
  Na  Na1  1  0.500  0.500  0.204  1.0
  Na  Na2  1  1.000  0.500  0.296  1.0
  Na  Na3  1  0.500  0.500  0.796  1.0
  H  H4  1  0.538  0.134  0.632  1.0
  H  H5  1  0.962  0.134  0.132  1.0
  H  H6  1  0.462  0.866  0.368  1.0
  H  H7  1  0.038  0.866  0.868  1.0
  Se  Se8  1  0.275  0.086  0.562  1.0
  Se  Se9  1  0.225  0.086  0.062  1.0
  Se  Se10  1  0.725  0.914  0.438  1.0
  Se  Se11  1  0.775  0.914  0.938  1.0
  O  O12  1  0.108  0.273  0.549  1.0
  O  O13  1  0.392  0.273  0.049  1.0
  O  O14  1  0.892  0.727  0.451  1.0
  O  O15  1  0.608  0.727  0.951  1.0
  O  O16  1  0.254  0.769  0.678  1.0
  O  O17  1  0.246  0.769  0.178  1.0
  O  O18  1  0.746  0.231  0.322  1.0
  O  O19  1  0.754  0.231  0.822  1.0
  O  O20  1  0.343  0.120  0.391  1.0
  O  O21  1  0.157  0.120  0.891  1.0
  O  O22  1  0.657  0.880  0.609  1.0
  O  O23  1  0.843  0.880  0.109  1.0
  O  O24  1  0.432  0.234  0.639  1.0
  O  O25  1  0.068  0.234  0.139  1.0
  O  O26  1  0.568  0.766  0.361  1.0
  O  O27  1  0.932  0.766  0.861  1.0
[/CIF]
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