The crystal structure described by K2Ce2Fe4O11 crystallizes in the orthorhombic Cmmm space group. K(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, faces with four equivalent K(1)O12 cuboctahedra, faces with four equivalent Fe(2)O6 octahedra, and faces with four equivalent Fe(1)O5 trigonal bipyramids. Ce(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and four equivalent O(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted FeO5 trigonal bipyramids that share corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, and faces with four equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-30°. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Fe(1)O5 trigonal bipyramids, and faces with four equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-18°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ce(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ce(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Ce(1), and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded to four equivalent K(1), one Fe(1), and one Fe(2) atom to form a mixture of distorted corner and edge-sharing OK4Fe2 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Ce(1) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_K2Ce2Fe4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.817
_cell_length_b   8.817
_cell_length_c   3.899
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   126.681
_symmetry_Int_Tables_number   1
_cell_volume   243.103
_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  0.500  0.000  0.500  1.0
  K  K1  1  0.000  0.500  0.500  1.0
  Ce  Ce2  1  0.234  0.234  0.500  1.0
  Ce  Ce3  1  0.766  0.766  0.500  1.0
  Fe  Fe4  1  0.630  0.370  0.000  1.0
  Fe  Fe5  1  0.370  0.630  0.000  1.0
  Fe  Fe6  1  0.873  0.127  0.000  1.0
  Fe  Fe7  1  0.127  0.873  0.000  1.0
  O  O8  1  0.356  0.167  0.000  1.0
  O  O9  1  0.833  0.644  0.000  1.0
  O  O10  1  0.644  0.833  0.000  1.0
  O  O11  1  0.167  0.356  0.000  1.0
  O  O12  1  0.586  0.414  0.500  1.0
  O  O13  1  0.414  0.586  0.500  1.0
  O  O14  1  0.893  0.107  0.500  1.0
  O  O15  1  0.107  0.893  0.500  1.0
  O  O16  1  0.750  0.250  0.000  1.0
  O  O17  1  0.250  0.750  0.000  1.0
  O  O18  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by K2Ce2Fe4O11 crystallizes in the orthorhombic Cmmm space group. K(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, faces with four equivalent K(1)O12 cuboctahedra, faces with four equivalent Fe(2)O6 octahedra, and faces with four equivalent Fe(1)O5 trigonal bipyramids. Ce(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(5), and four equivalent O(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(2) atoms to form distorted FeO5 trigonal bipyramids that share corners with three equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, and faces with four equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-30°. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Fe(1)O5 trigonal bipyramids, and faces with four equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-18°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ce(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ce(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Ce(1), and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded to four equivalent K(1), one Fe(1), and one Fe(2) atom to form a mixture of distorted corner and edge-sharing OK4Fe2 octahedra. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Ce(1) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_K2Ce2Fe4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.817
_cell_length_b   8.817
_cell_length_c   3.899
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   126.681
_symmetry_Int_Tables_number   1
_cell_volume   243.103
_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  0.500  0.000  0.500  1.0
  K  K1  1  0.000  0.500  0.500  1.0
  Ce  Ce2  1  0.234  0.234  0.500  1.0
  Ce  Ce3  1  0.766  0.766  0.500  1.0
  Fe  Fe4  1  0.630  0.370  0.000  1.0
  Fe  Fe5  1  0.370  0.630  0.000  1.0
  Fe  Fe6  1  0.873  0.127  0.000  1.0
  Fe  Fe7  1  0.127  0.873  0.000  1.0
  O  O8  1  0.356  0.167  0.000  1.0
  O  O9  1  0.833  0.644  0.000  1.0
  O  O10  1  0.644  0.833  0.000  1.0
  O  O11  1  0.167  0.356  0.000  1.0
  O  O12  1  0.586  0.414  0.500  1.0
  O  O13  1  0.414  0.586  0.500  1.0
  O  O14  1  0.893  0.107  0.500  1.0
  O  O15  1  0.107  0.893  0.500  1.0
  O  O16  1  0.750  0.250  0.000  1.0
  O  O17  1  0.250  0.750  0.000  1.0
  O  O18  1  0.000  0.000  0.000  1.0
[/CIF]
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