The compound described by K2Se4O crystallizes in the monoclinic Cc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 1-coordinate geometry to one Se(2), two equivalent Se(1), two equivalent Se(3), and one O(1) atom. In the second K site, K(2) is bonded in a 1-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), and one O(1) atom. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted pentagonal planar geometry to one K(2), two equivalent K(1), one Se(2), and one Se(3) atom. In the second Se site, Se(2) is bonded in a see-saw-like geometry to one K(1), one K(2), one Se(1), and one Se(4) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent K(1), two equivalent K(2), and one Se(1) atom. In the fourth Se site, Se(4) is bonded in a single-bond geometry to one Se(2) and one O(1) atom. O(1) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one Se(4) atom. is represented by the CIF file [CIF]
data_K2Se4O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.375
_cell_length_b   6.375
_cell_length_c   11.309
_cell_angle_alpha   82.949
_cell_angle_beta   82.949
_cell_angle_gamma   85.745
_symmetry_Int_Tables_number   1
_cell_volume   451.796
_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  0.094  0.648  0.671  1.0
  K  K1  1  0.648  0.094  0.171  1.0
  K  K2  1  0.125  0.505  0.058  1.0
  K  K3  1  0.505  0.125  0.558  1.0
  Se  Se4  1  0.580  0.524  0.808  1.0
  Se  Se5  1  0.524  0.580  0.308  1.0
  Se  Se6  1  0.669  0.143  0.846  1.0
  Se  Se7  1  0.143  0.669  0.346  1.0
  Se  Se8  1  0.618  0.610  0.594  1.0
  Se  Se9  1  0.610  0.618  0.094  1.0
  Se  Se10  1  0.044  0.087  0.845  1.0
  Se  Se11  1  0.087  0.044  0.345  1.0
  O  O12  1  0.157  0.058  0.699  1.0
  O  O13  1  0.058  0.157  0.199  1.0
[/CIF]
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The compound described by K2Se4O crystallizes in the monoclinic Cc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 1-coordinate geometry to one Se(2), two equivalent Se(1), two equivalent Se(3), and one O(1) atom. In the second K site, K(2) is bonded in a 1-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), and one O(1) atom. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted pentagonal planar geometry to one K(2), two equivalent K(1), one Se(2), and one Se(3) atom. In the second Se site, Se(2) is bonded in a see-saw-like geometry to one K(1), one K(2), one Se(1), and one Se(4) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent K(1), two equivalent K(2), and one Se(1) atom. In the fourth Se site, Se(4) is bonded in a single-bond geometry to one Se(2) and one O(1) atom. O(1) is bonded in a distorted trigonal non-coplanar geometry to one K(1), one K(2), and one Se(4) atom. is represented by the CIF file [CIF]
data_K2Se4O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.375
_cell_length_b   6.375
_cell_length_c   11.309
_cell_angle_alpha   82.949
_cell_angle_beta   82.949
_cell_angle_gamma   85.745
_symmetry_Int_Tables_number   1
_cell_volume   451.796
_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  0.094  0.648  0.671  1.0
  K  K1  1  0.648  0.094  0.171  1.0
  K  K2  1  0.125  0.505  0.058  1.0
  K  K3  1  0.505  0.125  0.558  1.0
  Se  Se4  1  0.580  0.524  0.808  1.0
  Se  Se5  1  0.524  0.580  0.308  1.0
  Se  Se6  1  0.669  0.143  0.846  1.0
  Se  Se7  1  0.143  0.669  0.346  1.0
  Se  Se8  1  0.618  0.610  0.594  1.0
  Se  Se9  1  0.610  0.618  0.094  1.0
  Se  Se10  1  0.044  0.087  0.845  1.0
  Se  Se11  1  0.087  0.044  0.345  1.0
  O  O12  1  0.157  0.058  0.699  1.0
  O  O13  1  0.058  0.157  0.199  1.0
[/CIF]
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