The material described by KCr2Fe(HO4)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CrO4 tetrahedra that share corners with two equivalent Fe(1)H2O4 octahedra. The corner-sharing octahedral tilt angles are 41°. Fe(1) is bonded to two equivalent H(1) and four equivalent O(1) atoms to form FeH2O4 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra. H(1) is bonded in a single-bond geometry to one Fe(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Cr(1), and one Fe(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_KCr2Fe(HO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.119
_cell_length_b   6.119
_cell_length_c   7.793
_cell_angle_alpha   68.420
_cell_angle_beta   68.420
_cell_angle_gamma   53.880
_symmetry_Int_Tables_number   1
_cell_volume   214.661
_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  0.500  1.0
  Cr  Cr1  1  0.394  0.394  0.282  1.0
  Cr  Cr2  1  0.606  0.606  0.718  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  H  H4  1  0.825  0.825  0.076  1.0
  H  H5  1  0.175  0.175  0.924  1.0
  O  O6  1  0.743  0.229  0.185  1.0
  O  O7  1  0.257  0.771  0.815  1.0
  O  O8  1  0.771  0.257  0.815  1.0
  O  O9  1  0.229  0.743  0.185  1.0
  O  O10  1  0.644  0.644  0.493  1.0
  O  O11  1  0.356  0.356  0.507  1.0
  O  O12  1  0.259  0.259  0.245  1.0
  O  O13  1  0.741  0.741  0.755  1.0
[/CIF]
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The material described by KCr2Fe(HO4)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. Cr(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form CrO4 tetrahedra that share corners with two equivalent Fe(1)H2O4 octahedra. The corner-sharing octahedral tilt angles are 41°. Fe(1) is bonded to two equivalent H(1) and four equivalent O(1) atoms to form FeH2O4 octahedra that share corners with four equivalent Cr(1)O4 tetrahedra. H(1) is bonded in a single-bond geometry to one Fe(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one Cr(1), and one Fe(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to two equivalent K(1) and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_KCr2Fe(HO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.119
_cell_length_b   6.119
_cell_length_c   7.793
_cell_angle_alpha   68.420
_cell_angle_beta   68.420
_cell_angle_gamma   53.880
_symmetry_Int_Tables_number   1
_cell_volume   214.661
_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  0.500  1.0
  Cr  Cr1  1  0.394  0.394  0.282  1.0
  Cr  Cr2  1  0.606  0.606  0.718  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  H  H4  1  0.825  0.825  0.076  1.0
  H  H5  1  0.175  0.175  0.924  1.0
  O  O6  1  0.743  0.229  0.185  1.0
  O  O7  1  0.257  0.771  0.815  1.0
  O  O8  1  0.771  0.257  0.815  1.0
  O  O9  1  0.229  0.743  0.185  1.0
  O  O10  1  0.644  0.644  0.493  1.0
  O  O11  1  0.356  0.356  0.507  1.0
  O  O12  1  0.259  0.259  0.245  1.0
  O  O13  1  0.741  0.741  0.755  1.0
[/CIF]
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