The structure described by KFe3(SO7)2 crystallizes in the trigonal R3m space group. K(1) is bonded to three equivalent O(3), three equivalent O(4), three equivalent O(5), and three equivalent O(6) atoms to form KO12 cuboctahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and faces with six equivalent Fe(1)O6 octahedra. Fe(1) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and faces with two equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 40-46°. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1) and three equivalent O(3) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the second S site, S(2) is bonded to one O(2) and three equivalent O(4) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one S(2) atom. In the third O site, O(3) is bonded in a 3-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 3-coordinate geometry to one K(1), one Fe(1), and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1) and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_KFe3(SO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.641
_cell_length_b   7.641
_cell_length_c   7.641
_cell_angle_alpha   54.518
_cell_angle_beta   54.518
_cell_angle_gamma   54.518
_symmetry_Int_Tables_number   1
_cell_volume   275.139
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.003  0.487  0.003  1.0
  Fe  Fe2  1  0.003  0.003  0.487  1.0
  Fe  Fe3  1  0.487  0.003  0.003  1.0
  S  S4  1  0.703  0.703  0.703  1.0
  S  S5  1  0.296  0.296  0.296  1.0
  O  O6  1  0.629  0.629  0.629  1.0
  O  O7  1  0.371  0.371  0.371  1.0
  O  O8  1  0.847  0.496  0.847  1.0
  O  O9  1  0.847  0.847  0.496  1.0
  O  O10  1  0.496  0.847  0.847  1.0
  O  O11  1  0.153  0.502  0.153  1.0
  O  O12  1  0.153  0.153  0.502  1.0
  O  O13  1  0.502  0.153  0.153  1.0
  O  O14  1  0.749  0.083  0.749  1.0
  O  O15  1  0.749  0.749  0.083  1.0
  O  O16  1  0.083  0.749  0.749  1.0
  O  O17  1  0.271  0.886  0.271  1.0
  O  O18  1  0.271  0.271  0.886  1.0
  O  O19  1  0.886  0.271  0.271  1.0
[/CIF]
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The structure described by KFe3(SO7)2 crystallizes in the trigonal R3m space group. K(1) is bonded to three equivalent O(3), three equivalent O(4), three equivalent O(5), and three equivalent O(6) atoms to form KO12 cuboctahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, and faces with six equivalent Fe(1)O6 octahedra. Fe(1) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one S(1)O4 tetrahedra,  a cornercorner with one S(2)O4 tetrahedra, and faces with two equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 40-46°. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(1) and three equivalent O(3) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the second S site, S(2) is bonded to one O(2) and three equivalent O(4) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one S(2) atom. In the third O site, O(3) is bonded in a 3-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 3-coordinate geometry to one K(1), one Fe(1), and one S(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1) and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_KFe3(SO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.641
_cell_length_b   7.641
_cell_length_c   7.641
_cell_angle_alpha   54.518
_cell_angle_beta   54.518
_cell_angle_gamma   54.518
_symmetry_Int_Tables_number   1
_cell_volume   275.139
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.003  0.487  0.003  1.0
  Fe  Fe2  1  0.003  0.003  0.487  1.0
  Fe  Fe3  1  0.487  0.003  0.003  1.0
  S  S4  1  0.703  0.703  0.703  1.0
  S  S5  1  0.296  0.296  0.296  1.0
  O  O6  1  0.629  0.629  0.629  1.0
  O  O7  1  0.371  0.371  0.371  1.0
  O  O8  1  0.847  0.496  0.847  1.0
  O  O9  1  0.847  0.847  0.496  1.0
  O  O10  1  0.496  0.847  0.847  1.0
  O  O11  1  0.153  0.502  0.153  1.0
  O  O12  1  0.153  0.153  0.502  1.0
  O  O13  1  0.502  0.153  0.153  1.0
  O  O14  1  0.749  0.083  0.749  1.0
  O  O15  1  0.749  0.749  0.083  1.0
  O  O16  1  0.083  0.749  0.749  1.0
  O  O17  1  0.271  0.886  0.271  1.0
  O  O18  1  0.271  0.271  0.886  1.0
  O  O19  1  0.886  0.271  0.271  1.0
[/CIF]
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