The compound described by KFeS2O9 crystallizes in the monoclinic P2_1/m space group. K(1) is bonded in a 10-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), two equivalent O(6), and three equivalent O(5) atoms. Fe(1) is bonded to one O(4), one O(7), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 40°. In the second S site, S(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-45°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one K(1) and one S(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to two equivalent K(1) and one S(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(2) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(2) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Fe(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeS2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.209
_cell_length_b   8.106
_cell_length_c   9.248
_cell_angle_alpha   77.146
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   380.656
_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  0.424  0.217  1.0
  K  K1  1  0.750  0.576  0.783  1.0
  Fe  Fe2  1  0.250  0.912  0.226  1.0
  Fe  Fe3  1  0.750  0.088  0.774  1.0
  S  S4  1  0.250  0.332  0.654  1.0
  S  S5  1  0.750  0.668  0.346  1.0
  S  S6  1  0.250  0.846  0.882  1.0
  S  S7  1  0.750  0.154  0.118  1.0
  O  O8  1  0.250  0.261  0.520  1.0
  O  O9  1  0.750  0.739  0.480  1.0
  O  O10  1  0.250  0.517  0.624  1.0
  O  O11  1  0.750  0.483  0.376  1.0
  O  O12  1  0.017  0.270  0.749  1.0
  O  O13  1  0.517  0.730  0.251  1.0
  O  O14  1  0.983  0.730  0.251  1.0
  O  O15  1  0.483  0.270  0.749  1.0
  O  O16  1  0.250  0.937  0.005  1.0
  O  O17  1  0.750  0.063  0.995  1.0
  O  O18  1  0.250  0.662  0.934  1.0
  O  O19  1  0.750  0.338  0.066  1.0
  O  O20  1  0.016  0.900  0.788  1.0
  O  O21  1  0.516  0.100  0.212  1.0
  O  O22  1  0.984  0.100  0.212  1.0
  O  O23  1  0.484  0.900  0.788  1.0
  O  O24  1  0.250  0.893  0.454  1.0
  O  O25  1  0.750  0.107  0.546  1.0
[/CIF]
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The compound described by KFeS2O9 crystallizes in the monoclinic P2_1/m space group. K(1) is bonded in a 10-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), two equivalent O(6), and three equivalent O(5) atoms. Fe(1) is bonded to one O(4), one O(7), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 40°. In the second S site, S(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 35-45°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one K(1) and one S(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to two equivalent K(1) and one S(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to three equivalent K(1) and one S(2) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one K(1), one Fe(1), and one S(2) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Fe(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KFeS2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.209
_cell_length_b   8.106
_cell_length_c   9.248
_cell_angle_alpha   77.146
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   380.656
_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  0.424  0.217  1.0
  K  K1  1  0.750  0.576  0.783  1.0
  Fe  Fe2  1  0.250  0.912  0.226  1.0
  Fe  Fe3  1  0.750  0.088  0.774  1.0
  S  S4  1  0.250  0.332  0.654  1.0
  S  S5  1  0.750  0.668  0.346  1.0
  S  S6  1  0.250  0.846  0.882  1.0
  S  S7  1  0.750  0.154  0.118  1.0
  O  O8  1  0.250  0.261  0.520  1.0
  O  O9  1  0.750  0.739  0.480  1.0
  O  O10  1  0.250  0.517  0.624  1.0
  O  O11  1  0.750  0.483  0.376  1.0
  O  O12  1  0.017  0.270  0.749  1.0
  O  O13  1  0.517  0.730  0.251  1.0
  O  O14  1  0.983  0.730  0.251  1.0
  O  O15  1  0.483  0.270  0.749  1.0
  O  O16  1  0.250  0.937  0.005  1.0
  O  O17  1  0.750  0.063  0.995  1.0
  O  O18  1  0.250  0.662  0.934  1.0
  O  O19  1  0.750  0.338  0.066  1.0
  O  O20  1  0.016  0.900  0.788  1.0
  O  O21  1  0.516  0.100  0.212  1.0
  O  O22  1  0.984  0.100  0.212  1.0
  O  O23  1  0.484  0.900  0.788  1.0
  O  O24  1  0.250  0.893  0.454  1.0
  O  O25  1  0.750  0.107  0.546  1.0
[/CIF]
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