The material described by Rb2Cr4Cu(HO4)4 crystallizes in the triclinic P-1 space group. Rb(1) is bonded in a 11-coordinate geometry to one H(1), one O(1), one O(2), one O(4), one O(7), two equivalent O(5), two equivalent O(6), and two equivalent O(8) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and  a cornercorner with one Cr(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. Cu(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(7) atoms to form distorted CuO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and corners with two equivalent Cr(2)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one Rb(1) and one O(3) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Rb(1), one Cr(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), one Cr(2), and one Cu(1) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one Cu(1), one H(1), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1) and one Cr(1) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to two equivalent Rb(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Cr(1), and one Cu(1) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one Cr(1) atom. is represented by the CIF file [CIF]
data_Rb2Cr4Cu(HO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.605
_cell_length_b   7.749
_cell_length_c   7.794
_cell_angle_alpha   92.047
_cell_angle_beta   117.044
_cell_angle_gamma   98.764
_symmetry_Int_Tables_number   1
_cell_volume   401.464
_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
  Rb  Rb0  1  0.755  0.844  0.268  1.0
  Rb  Rb1  1  0.245  0.156  0.732  1.0
  Cr  Cr2  1  0.754  0.331  0.522  1.0
  Cr  Cr3  1  0.699  0.850  0.756  1.0
  Cr  Cr4  1  0.246  0.669  0.478  1.0
  Cr  Cr5  1  0.301  0.150  0.244  1.0
  Cu  Cu6  1  0.000  0.500  0.000  1.0
  H  H7  1  0.671  0.372  0.963  1.0
  H  H8  1  0.770  0.205  0.987  1.0
  H  H9  1  0.329  0.628  0.037  1.0
  H  H10  1  0.230  0.795  0.013  1.0
  O  O11  1  0.513  0.214  0.479  1.0
  O  O12  1  0.742  0.676  0.872  1.0
  O  O13  1  0.796  0.332  0.041  1.0
  O  O14  1  0.725  0.517  0.435  1.0
  O  O15  1  0.889  0.934  0.722  1.0
  O  O16  1  0.258  0.324  0.128  1.0
  O  O17  1  0.348  0.003  0.118  1.0
  O  O18  1  0.084  0.642  0.241  1.0
  O  O19  1  0.275  0.483  0.565  1.0
  O  O20  1  0.111  0.066  0.278  1.0
  O  O21  1  0.652  0.997  0.882  1.0
  O  O22  1  0.204  0.668  0.959  1.0
  O  O23  1  0.840  0.214  0.411  1.0
  O  O24  1  0.160  0.786  0.589  1.0
  O  O25  1  0.487  0.786  0.521  1.0
  O  O26  1  0.916  0.358  0.759  1.0
[/CIF]
.
The material described by Rb2Cr4Cu(HO4)4 crystallizes in the triclinic P-1 space group. Rb(1) is bonded in a 11-coordinate geometry to one H(1), one O(1), one O(2), one O(4), one O(7), two equivalent O(5), two equivalent O(6), and two equivalent O(8) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(4), one O(7), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and  a cornercorner with one Cr(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. Cu(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(7) atoms to form distorted CuO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and corners with two equivalent Cr(2)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one Rb(1) and one O(3) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Rb(1), one Cr(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), one Cr(2), and one Cu(1) atom. In the third O site, O(3) is bonded in a distorted water-like geometry to one Cu(1), one H(1), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1) and one Cr(1) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to two equivalent Rb(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Cr(1), and one Cu(1) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Rb(1) and one Cr(1) atom. is represented by the CIF file [CIF]
data_Rb2Cr4Cu(HO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.605
_cell_length_b   7.749
_cell_length_c   7.794
_cell_angle_alpha   92.047
_cell_angle_beta   117.044
_cell_angle_gamma   98.764
_symmetry_Int_Tables_number   1
_cell_volume   401.464
_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
  Rb  Rb0  1  0.755  0.844  0.268  1.0
  Rb  Rb1  1  0.245  0.156  0.732  1.0
  Cr  Cr2  1  0.754  0.331  0.522  1.0
  Cr  Cr3  1  0.699  0.850  0.756  1.0
  Cr  Cr4  1  0.246  0.669  0.478  1.0
  Cr  Cr5  1  0.301  0.150  0.244  1.0
  Cu  Cu6  1  0.000  0.500  0.000  1.0
  H  H7  1  0.671  0.372  0.963  1.0
  H  H8  1  0.770  0.205  0.987  1.0
  H  H9  1  0.329  0.628  0.037  1.0
  H  H10  1  0.230  0.795  0.013  1.0
  O  O11  1  0.513  0.214  0.479  1.0
  O  O12  1  0.742  0.676  0.872  1.0
  O  O13  1  0.796  0.332  0.041  1.0
  O  O14  1  0.725  0.517  0.435  1.0
  O  O15  1  0.889  0.934  0.722  1.0
  O  O16  1  0.258  0.324  0.128  1.0
  O  O17  1  0.348  0.003  0.118  1.0
  O  O18  1  0.084  0.642  0.241  1.0
  O  O19  1  0.275  0.483  0.565  1.0
  O  O20  1  0.111  0.066  0.278  1.0
  O  O21  1  0.652  0.997  0.882  1.0
  O  O22  1  0.204  0.668  0.959  1.0
  O  O23  1  0.840  0.214  0.411  1.0
  O  O24  1  0.160  0.786  0.589  1.0
  O  O25  1  0.487  0.786  0.521  1.0
  O  O26  1  0.916  0.358  0.759  1.0
[/CIF]
.