The structure described by K2S2O5 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted edge-sharing KO7 pentagonal bipyramids. In the second K site, K(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(1), and four equivalent O(3) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded in a water-like geometry to two equivalent O(3) atoms. In the second S site, S(2) is bonded in a trigonal non-coplanar geometry to one O(1) and two equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one K(1), three equivalent K(2), and one S(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), and one S(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one S(1) atom. is represented by the CIF file [CIF]
data_K2S2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.229
_cell_length_b   7.169
_cell_length_c   7.731
_cell_angle_alpha   78.437
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   338.234
_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  0.250  0.356  0.674  1.0
  K  K1  1  0.750  0.644  0.326  1.0
  K  K2  1  0.250  0.784  0.929  1.0
  K  K3  1  0.750  0.216  0.071  1.0
  S  S4  1  0.250  0.972  0.319  1.0
  S  S5  1  0.750  0.028  0.681  1.0
  S  S6  1  0.250  0.304  0.239  1.0
  S  S7  1  0.750  0.696  0.761  1.0
  O  O8  1  0.250  0.359  0.043  1.0
  O  O9  1  0.750  0.641  0.957  1.0
  O  O10  1  0.552  0.633  0.681  1.0
  O  O11  1  0.052  0.367  0.319  1.0
  O  O12  1  0.448  0.367  0.319  1.0
  O  O13  1  0.948  0.633  0.681  1.0
  O  O14  1  0.551  0.072  0.776  1.0
  O  O15  1  0.051  0.928  0.224  1.0
  O  O16  1  0.949  0.072  0.776  1.0
  O  O17  1  0.449  0.928  0.224  1.0
[/CIF]
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The structure described by K2S2O5 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted edge-sharing KO7 pentagonal bipyramids. In the second K site, K(2) is bonded in a 9-coordinate geometry to two equivalent O(2), three equivalent O(1), and four equivalent O(3) atoms. There are two inequivalent S sites. In the first S site, S(1) is bonded in a water-like geometry to two equivalent O(3) atoms. In the second S site, S(2) is bonded in a trigonal non-coplanar geometry to one O(1) and two equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one K(1), three equivalent K(2), and one S(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(2), two equivalent K(1), and one S(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one S(1) atom. is represented by the CIF file [CIF]
data_K2S2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.229
_cell_length_b   7.169
_cell_length_c   7.731
_cell_angle_alpha   78.437
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   338.234
_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  0.250  0.356  0.674  1.0
  K  K1  1  0.750  0.644  0.326  1.0
  K  K2  1  0.250  0.784  0.929  1.0
  K  K3  1  0.750  0.216  0.071  1.0
  S  S4  1  0.250  0.972  0.319  1.0
  S  S5  1  0.750  0.028  0.681  1.0
  S  S6  1  0.250  0.304  0.239  1.0
  S  S7  1  0.750  0.696  0.761  1.0
  O  O8  1  0.250  0.359  0.043  1.0
  O  O9  1  0.750  0.641  0.957  1.0
  O  O10  1  0.552  0.633  0.681  1.0
  O  O11  1  0.052  0.367  0.319  1.0
  O  O12  1  0.448  0.367  0.319  1.0
  O  O13  1  0.948  0.633  0.681  1.0
  O  O14  1  0.551  0.072  0.776  1.0
  O  O15  1  0.051  0.928  0.224  1.0
  O  O16  1  0.949  0.072  0.776  1.0
  O  O17  1  0.449  0.928  0.224  1.0
[/CIF]
.