The compound described by K2S2O7 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 9-coordinate geometry to three equivalent O(1), three equivalent O(2), and three equivalent O(3) atoms. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent S(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2S2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.122
_cell_length_b   7.122
_cell_length_c   7.262
_cell_angle_alpha   86.631
_cell_angle_beta   86.631
_cell_angle_gamma   61.399
_symmetry_Int_Tables_number   1
_cell_volume   322.676
_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
  K  K0  1  0.500  0.206  0.858  1.0
  K  K1  1  0.206  0.500  0.358  1.0
  K  K2  1  0.794  0.500  0.642  1.0
  K  K3  1  0.500  0.794  0.142  1.0
  S  S4  1  0.717  0.077  0.362  1.0
  S  S5  1  0.923  0.283  0.138  1.0
  S  S6  1  0.283  0.923  0.638  1.0
  S  S7  1  0.077  0.717  0.862  1.0
  O  O8  1  0.143  0.194  0.074  1.0
  O  O9  1  0.806  0.857  0.426  1.0
  O  O10  1  0.446  0.860  0.773  1.0
  O  O11  1  0.140  0.554  0.727  1.0
  O  O12  1  0.857  0.806  0.926  1.0
  O  O13  1  0.230  0.655  0.005  1.0
  O  O14  1  0.074  0.926  0.750  1.0
  O  O15  1  0.345  0.770  0.495  1.0
  O  O16  1  0.770  0.345  0.995  1.0
  O  O17  1  0.860  0.446  0.273  1.0
  O  O18  1  0.554  0.140  0.227  1.0
  O  O19  1  0.926  0.074  0.250  1.0
  O  O20  1  0.655  0.230  0.505  1.0
  O  O21  1  0.194  0.143  0.574  1.0
[/CIF]
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The compound described by K2S2O7 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 9-coordinate geometry to three equivalent O(1), three equivalent O(2), and three equivalent O(3) atoms. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent S(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2S2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.122
_cell_length_b   7.122
_cell_length_c   7.262
_cell_angle_alpha   86.631
_cell_angle_beta   86.631
_cell_angle_gamma   61.399
_symmetry_Int_Tables_number   1
_cell_volume   322.676
_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
  K  K0  1  0.500  0.206  0.858  1.0
  K  K1  1  0.206  0.500  0.358  1.0
  K  K2  1  0.794  0.500  0.642  1.0
  K  K3  1  0.500  0.794  0.142  1.0
  S  S4  1  0.717  0.077  0.362  1.0
  S  S5  1  0.923  0.283  0.138  1.0
  S  S6  1  0.283  0.923  0.638  1.0
  S  S7  1  0.077  0.717  0.862  1.0
  O  O8  1  0.143  0.194  0.074  1.0
  O  O9  1  0.806  0.857  0.426  1.0
  O  O10  1  0.446  0.860  0.773  1.0
  O  O11  1  0.140  0.554  0.727  1.0
  O  O12  1  0.857  0.806  0.926  1.0
  O  O13  1  0.230  0.655  0.005  1.0
  O  O14  1  0.074  0.926  0.750  1.0
  O  O15  1  0.345  0.770  0.495  1.0
  O  O16  1  0.770  0.345  0.995  1.0
  O  O17  1  0.860  0.446  0.273  1.0
  O  O18  1  0.554  0.140  0.227  1.0
  O  O19  1  0.926  0.074  0.250  1.0
  O  O20  1  0.655  0.230  0.505  1.0
  O  O21  1  0.194  0.143  0.574  1.0
[/CIF]
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