The material described by K2H2P2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(6) atom. In the second K site, K(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(7), and two equivalent O(1) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(2), one O(3), one O(4), and one O(7) atom. In the second P site, P(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(5), and one O(6) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a linear geometry to one O(3) and one O(5) atom. In the second H site, H(2) is bonded in a linear geometry to one O(2) and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one O(7) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(1), one K(2), one P(1), and one H(2) atom. In the third O site, O(3) is bonded in a water-like geometry to one K(2), one P(1), and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(2), one P(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(1), one P(2), and one H(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one K(1), one P(2), and one H(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one K(2), one P(1), and one O(1) atom. is represented by the CIF card [CIF]
data_K2P2H2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.782
_cell_length_b   9.050
_cell_length_c   7.257
_cell_angle_alpha   105.861
_cell_angle_beta   100.337
_cell_angle_gamma   111.559
_symmetry_Int_Tables_number   1
_cell_volume   434.313
_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
  K  K0  1  0.216  0.097  0.824  1.0
  K  K1  1  0.784  0.903  0.176  1.0
  K  K2  1  0.699  0.458  0.221  1.0
  K  K3  1  0.301  0.542  0.779  1.0
  P  P4  1  0.644  0.316  0.682  1.0
  P  P5  1  0.356  0.684  0.318  1.0
  P  P6  1  0.248  0.088  0.330  1.0
  P  P7  1  0.752  0.912  0.670  1.0
  H  H8  1  0.152  0.782  0.375  1.0
  H  H9  1  0.848  0.218  0.625  1.0
  H  H10  1  0.673  0.099  0.863  1.0
  H  H11  1  0.327  0.901  0.137  1.0
  O  O12  1  0.714  0.605  0.937  1.0
  O  O13  1  0.286  0.395  0.063  1.0
  O  O14  1  0.404  0.761  0.164  1.0
  O  O15  1  0.596  0.239  0.836  1.0
  O  O16  1  0.849  0.343  0.659  1.0
  O  O17  1  0.151  0.657  0.341  1.0
  O  O18  1  0.500  0.204  0.461  1.0
  O  O19  1  0.500  0.796  0.539  1.0
  O  O20  1  0.172  0.952  0.425  1.0
  O  O21  1  0.828  0.048  0.575  1.0
  O  O22  1  0.281  0.990  0.123  1.0
  O  O23  1  0.719  0.010  0.877  1.0
  O  O24  1  0.625  0.491  0.719  1.0
  O  O25  1  0.375  0.509  0.281  1.0
[/CIF]
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The material described by K2H2P2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(5), and one O(6) atom. In the second K site, K(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(7), and two equivalent O(1) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded in a tetrahedral geometry to one O(2), one O(3), one O(4), and one O(7) atom. In the second P site, P(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(5), and one O(6) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a linear geometry to one O(3) and one O(5) atom. In the second H site, H(2) is bonded in a linear geometry to one O(2) and one O(6) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), two equivalent K(2), and one O(7) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(1), one K(2), one P(1), and one H(2) atom. In the third O site, O(3) is bonded in a water-like geometry to one K(2), one P(1), and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(2), one P(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(1), one P(2), and one H(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one K(1), one P(2), and one H(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one K(2), one P(1), and one O(1) atom. is represented by the CIF card [CIF]
data_K2P2H2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.782
_cell_length_b   9.050
_cell_length_c   7.257
_cell_angle_alpha   105.861
_cell_angle_beta   100.337
_cell_angle_gamma   111.559
_symmetry_Int_Tables_number   1
_cell_volume   434.313
_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
  K  K0  1  0.216  0.097  0.824  1.0
  K  K1  1  0.784  0.903  0.176  1.0
  K  K2  1  0.699  0.458  0.221  1.0
  K  K3  1  0.301  0.542  0.779  1.0
  P  P4  1  0.644  0.316  0.682  1.0
  P  P5  1  0.356  0.684  0.318  1.0
  P  P6  1  0.248  0.088  0.330  1.0
  P  P7  1  0.752  0.912  0.670  1.0
  H  H8  1  0.152  0.782  0.375  1.0
  H  H9  1  0.848  0.218  0.625  1.0
  H  H10  1  0.673  0.099  0.863  1.0
  H  H11  1  0.327  0.901  0.137  1.0
  O  O12  1  0.714  0.605  0.937  1.0
  O  O13  1  0.286  0.395  0.063  1.0
  O  O14  1  0.404  0.761  0.164  1.0
  O  O15  1  0.596  0.239  0.836  1.0
  O  O16  1  0.849  0.343  0.659  1.0
  O  O17  1  0.151  0.657  0.341  1.0
  O  O18  1  0.500  0.204  0.461  1.0
  O  O19  1  0.500  0.796  0.539  1.0
  O  O20  1  0.172  0.952  0.425  1.0
  O  O21  1  0.828  0.048  0.575  1.0
  O  O22  1  0.281  0.990  0.123  1.0
  O  O23  1  0.719  0.010  0.877  1.0
  O  O24  1  0.625  0.491  0.719  1.0
  O  O25  1  0.375  0.509  0.281  1.0
[/CIF]
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