The structure described by KFeSeS crystallizes in the monoclinic C2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent S(1) atoms. In the second K site, K(2) is bonded to four equivalent Se(1) and four equivalent S(1) atoms to form distorted KSe4S4 hexagonal bipyramids that share corners with four equivalent K(2)Se4S4 hexagonal bipyramids, corners with two equivalent Fe(2)Se2S2 tetrahedra, corners with four equivalent Fe(1)Se2S2 tetrahedra, edges with two equivalent K(2)Se4S4 hexagonal bipyramids, edges with two equivalent Fe(1)Se2S2 tetrahedra, and edges with three equivalent Fe(2)Se2S2 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form FeSe2S2 tetrahedra that share corners with four equivalent K(2)Se4S4 hexagonal bipyramids, edges with two equivalent K(2)Se4S4 hexagonal bipyramids, and edges with two equivalent Fe(2)Se2S2 tetrahedra. In the second Fe site, Fe(2) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form FeSe2S2 tetrahedra that share corners with two equivalent K(2)Se4S4 hexagonal bipyramids, edges with three equivalent K(2)Se4S4 hexagonal bipyramids, and edges with two equivalent Fe(1)Se2S2 tetrahedra. Se(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Fe(1), and one Fe(2) atom. S(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_KFeSeS
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.863
_cell_length_b   6.863
_cell_length_c   5.484
_cell_angle_alpha   78.256
_cell_angle_beta   78.256
_cell_angle_gamma   116.891
_symmetry_Int_Tables_number   1
_cell_volume   212.217
_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  0.358  0.642  0.500  1.0
  K  K1  1  0.639  0.361  0.000  1.0
  Fe  Fe2  1  0.003  0.997  0.500  1.0
  Fe  Fe3  1  0.006  0.994  0.000  1.0
  Se  Se4  1  0.089  0.311  0.147  1.0
  Se  Se5  1  0.689  0.911  0.853  1.0
  S  S6  1  0.928  0.711  0.343  1.0
  S  S7  1  0.289  0.072  0.657  1.0
[/CIF]
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The structure described by KFeSeS crystallizes in the monoclinic C2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent S(1) atoms. In the second K site, K(2) is bonded to four equivalent Se(1) and four equivalent S(1) atoms to form distorted KSe4S4 hexagonal bipyramids that share corners with four equivalent K(2)Se4S4 hexagonal bipyramids, corners with two equivalent Fe(2)Se2S2 tetrahedra, corners with four equivalent Fe(1)Se2S2 tetrahedra, edges with two equivalent K(2)Se4S4 hexagonal bipyramids, edges with two equivalent Fe(1)Se2S2 tetrahedra, and edges with three equivalent Fe(2)Se2S2 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form FeSe2S2 tetrahedra that share corners with four equivalent K(2)Se4S4 hexagonal bipyramids, edges with two equivalent K(2)Se4S4 hexagonal bipyramids, and edges with two equivalent Fe(2)Se2S2 tetrahedra. In the second Fe site, Fe(2) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form FeSe2S2 tetrahedra that share corners with two equivalent K(2)Se4S4 hexagonal bipyramids, edges with three equivalent K(2)Se4S4 hexagonal bipyramids, and edges with two equivalent Fe(1)Se2S2 tetrahedra. Se(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Fe(1), and one Fe(2) atom. S(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_KFeSeS
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.863
_cell_length_b   6.863
_cell_length_c   5.484
_cell_angle_alpha   78.256
_cell_angle_beta   78.256
_cell_angle_gamma   116.891
_symmetry_Int_Tables_number   1
_cell_volume   212.217
_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  0.358  0.642  0.500  1.0
  K  K1  1  0.639  0.361  0.000  1.0
  Fe  Fe2  1  0.003  0.997  0.500  1.0
  Fe  Fe3  1  0.006  0.994  0.000  1.0
  Se  Se4  1  0.089  0.311  0.147  1.0
  Se  Se5  1  0.689  0.911  0.853  1.0
  S  S6  1  0.928  0.711  0.343  1.0
  S  S7  1  0.289  0.072  0.657  1.0
[/CIF]
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