The material described by RbH5(PO4)2 crystallizes in the monoclinic C2/c space group. Rb(1) is bonded in a distorted square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are three inequivalent H sites. In the first H site, H(1) is bonded in a linear geometry to two equivalent O(2) atoms. In the second H site, H(2) is bonded in a linear geometry to one O(1) and one O(4) atom. In the third H site, H(3) is bonded in a distorted linear geometry to one O(1) and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one P(1), one H(2), and one H(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one P(1), and one H(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one H(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one P(1), and one H(2) atom. is represented by the CIF file [CIF]
data_RbP2H5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.546
_cell_length_b   6.546
_cell_length_c   9.664
_cell_angle_alpha   81.441
_cell_angle_beta   81.441
_cell_angle_gamma   72.773
_symmetry_Int_Tables_number   1
_cell_volume   388.743
_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
  Rb  Rb0  1  0.000  0.000  0.500  1.0
  Rb  Rb1  1  0.000  0.000  0.000  1.0
  P  P2  1  0.268  0.368  0.701  1.0
  P  P3  1  0.632  0.732  0.799  1.0
  P  P4  1  0.732  0.632  0.299  1.0
  P  P5  1  0.368  0.268  0.201  1.0
  H  H6  1  0.308  0.692  0.750  1.0
  H  H7  1  0.692  0.308  0.250  1.0
  H  H8  1  0.923  0.443  0.673  1.0
  H  H9  1  0.557  0.077  0.827  1.0
  H  H10  1  0.077  0.557  0.327  1.0
  H  H11  1  0.443  0.923  0.173  1.0
  H  H12  1  0.389  0.292  0.487  1.0
  H  H13  1  0.708  0.611  0.013  1.0
  H  H14  1  0.611  0.708  0.513  1.0
  H  H15  1  0.292  0.389  0.987  1.0
  O  O16  1  0.353  0.269  0.841  1.0
  O  O17  1  0.731  0.647  0.659  1.0
  O  O18  1  0.647  0.731  0.159  1.0
  O  O19  1  0.269  0.353  0.341  1.0
  O  O20  1  0.219  0.616  0.679  1.0
  O  O21  1  0.384  0.781  0.821  1.0
  O  O22  1  0.781  0.384  0.321  1.0
  O  O23  1  0.616  0.219  0.179  1.0
  O  O24  1  0.443  0.258  0.583  1.0
  O  O25  1  0.742  0.557  0.917  1.0
  O  O26  1  0.557  0.742  0.417  1.0
  O  O27  1  0.258  0.443  0.083  1.0
  O  O28  1  0.056  0.311  0.681  1.0
  O  O29  1  0.689  0.944  0.819  1.0
  O  O30  1  0.944  0.689  0.319  1.0
  O  O31  1  0.311  0.056  0.181  1.0
[/CIF]
.
The material described by RbH5(PO4)2 crystallizes in the monoclinic C2/c space group. Rb(1) is bonded in a distorted square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. P(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are three inequivalent H sites. In the first H site, H(1) is bonded in a linear geometry to two equivalent O(2) atoms. In the second H site, H(2) is bonded in a linear geometry to one O(1) and one O(4) atom. In the third H site, H(3) is bonded in a distorted linear geometry to one O(1) and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one P(1), one H(2), and one H(3) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one P(1), and one H(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one H(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one P(1), and one H(2) atom. is represented by the CIF file [CIF]
data_RbP2H5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.546
_cell_length_b   6.546
_cell_length_c   9.664
_cell_angle_alpha   81.441
_cell_angle_beta   81.441
_cell_angle_gamma   72.773
_symmetry_Int_Tables_number   1
_cell_volume   388.743
_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
  Rb  Rb0  1  0.000  0.000  0.500  1.0
  Rb  Rb1  1  0.000  0.000  0.000  1.0
  P  P2  1  0.268  0.368  0.701  1.0
  P  P3  1  0.632  0.732  0.799  1.0
  P  P4  1  0.732  0.632  0.299  1.0
  P  P5  1  0.368  0.268  0.201  1.0
  H  H6  1  0.308  0.692  0.750  1.0
  H  H7  1  0.692  0.308  0.250  1.0
  H  H8  1  0.923  0.443  0.673  1.0
  H  H9  1  0.557  0.077  0.827  1.0
  H  H10  1  0.077  0.557  0.327  1.0
  H  H11  1  0.443  0.923  0.173  1.0
  H  H12  1  0.389  0.292  0.487  1.0
  H  H13  1  0.708  0.611  0.013  1.0
  H  H14  1  0.611  0.708  0.513  1.0
  H  H15  1  0.292  0.389  0.987  1.0
  O  O16  1  0.353  0.269  0.841  1.0
  O  O17  1  0.731  0.647  0.659  1.0
  O  O18  1  0.647  0.731  0.159  1.0
  O  O19  1  0.269  0.353  0.341  1.0
  O  O20  1  0.219  0.616  0.679  1.0
  O  O21  1  0.384  0.781  0.821  1.0
  O  O22  1  0.781  0.384  0.321  1.0
  O  O23  1  0.616  0.219  0.179  1.0
  O  O24  1  0.443  0.258  0.583  1.0
  O  O25  1  0.742  0.557  0.917  1.0
  O  O26  1  0.557  0.742  0.417  1.0
  O  O27  1  0.258  0.443  0.083  1.0
  O  O28  1  0.056  0.311  0.681  1.0
  O  O29  1  0.689  0.944  0.819  1.0
  O  O30  1  0.944  0.689  0.319  1.0
  O  O31  1  0.311  0.056  0.181  1.0
[/CIF]
.