The structure described by Na2S2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and  an edgeedge with one Na(2)O6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra and  a cornercorner with one S(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-59°. In the second S site, S(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra and  a cornercorner with one S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-63°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one S(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one S(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one S(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one S(1) and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one S(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Na(1), two equivalent Na(2), and one S(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2S2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.719
_cell_length_b   6.770
_cell_length_c   6.808
_cell_angle_alpha   83.715
_cell_angle_beta   63.188
_cell_angle_gamma   83.457
_symmetry_Int_Tables_number   1
_cell_volume   273.994
_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  0.774  0.863  0.176  1.0
  Na  Na1  1  0.226  0.137  0.824  1.0
  Na  Na2  1  0.383  0.334  0.243  1.0
  Na  Na3  1  0.617  0.666  0.757  1.0
  S  S4  1  0.268  0.841  0.251  1.0
  S  S5  1  0.732  0.159  0.749  1.0
  S  S6  1  0.141  0.639  0.688  1.0
  S  S7  1  0.859  0.361  0.312  1.0
  O  O8  1  0.237  0.445  0.608  1.0
  O  O9  1  0.763  0.555  0.392  1.0
  O  O10  1  0.709  0.242  0.286  1.0
  O  O11  1  0.291  0.758  0.714  1.0
  O  O12  1  0.917  0.641  0.864  1.0
  O  O13  1  0.083  0.359  0.136  1.0
  O  O14  1  0.085  0.760  0.490  1.0
  O  O15  1  0.915  0.240  0.510  1.0
  O  O16  1  0.384  0.991  0.287  1.0
  O  O17  1  0.616  0.009  0.713  1.0
  O  O18  1  0.582  0.329  0.850  1.0
  O  O19  1  0.418  0.671  0.150  1.0
  O  O20  1  0.876  0.082  0.850  1.0
  O  O21  1  0.124  0.918  0.150  1.0
[/CIF]
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The structure described by Na2S2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and  an edgeedge with one Na(2)O6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra and  a cornercorner with one S(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-59°. In the second S site, S(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with three equivalent Na(2)O6 octahedra and  a cornercorner with one S(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-63°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one S(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one S(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one S(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one S(1) and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Na(2), and one S(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Na(1), two equivalent Na(2), and one S(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2S2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.719
_cell_length_b   6.770
_cell_length_c   6.808
_cell_angle_alpha   83.715
_cell_angle_beta   63.188
_cell_angle_gamma   83.457
_symmetry_Int_Tables_number   1
_cell_volume   273.994
_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  0.774  0.863  0.176  1.0
  Na  Na1  1  0.226  0.137  0.824  1.0
  Na  Na2  1  0.383  0.334  0.243  1.0
  Na  Na3  1  0.617  0.666  0.757  1.0
  S  S4  1  0.268  0.841  0.251  1.0
  S  S5  1  0.732  0.159  0.749  1.0
  S  S6  1  0.141  0.639  0.688  1.0
  S  S7  1  0.859  0.361  0.312  1.0
  O  O8  1  0.237  0.445  0.608  1.0
  O  O9  1  0.763  0.555  0.392  1.0
  O  O10  1  0.709  0.242  0.286  1.0
  O  O11  1  0.291  0.758  0.714  1.0
  O  O12  1  0.917  0.641  0.864  1.0
  O  O13  1  0.083  0.359  0.136  1.0
  O  O14  1  0.085  0.760  0.490  1.0
  O  O15  1  0.915  0.240  0.510  1.0
  O  O16  1  0.384  0.991  0.287  1.0
  O  O17  1  0.616  0.009  0.713  1.0
  O  O18  1  0.582  0.329  0.850  1.0
  O  O19  1  0.418  0.671  0.150  1.0
  O  O20  1  0.876  0.082  0.850  1.0
  O  O21  1  0.124  0.918  0.150  1.0
[/CIF]
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