The material described by H2W2O7 crystallizes in the tetragonal I4_1/amd space group. W(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. H(1) is bonded in a single-bond geometry to one O(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent W(1) and one H(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent W(1) atoms. In the third O site, O(3) is bonded to four equivalent W(1) atoms to form corner-sharing OW4 tetrahedra. is represented by the CIF card [CIF]
data_H2W2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.063
_cell_length_b   7.063
_cell_length_c   7.063
_cell_angle_alpha   118.123
_cell_angle_beta   118.123
_cell_angle_gamma   93.283
_symmetry_Int_Tables_number   1
_cell_volume   255.794
_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
  H  H0  1  0.334  0.334  0.000  1.0
  H  H1  1  0.666  0.666  0.000  1.0
  H  H2  1  0.416  0.916  0.500  1.0
  H  H3  1  0.084  0.584  0.500  1.0
  W  W4  1  0.875  0.125  0.250  1.0
  W  W5  1  0.875  0.625  0.750  1.0
  W  W6  1  0.875  0.125  0.750  1.0
  W  W7  1  0.375  0.125  0.250  1.0
  O  O8  1  0.233  0.233  0.000  1.0
  O  O9  1  0.767  0.767  0.000  1.0
  O  O10  1  0.218  0.782  0.000  1.0
  O  O11  1  0.782  0.218  0.000  1.0
  O  O12  1  0.218  0.218  0.436  1.0
  O  O13  1  0.782  0.782  0.564  1.0
  O  O14  1  0.517  0.017  0.500  1.0
  O  O15  1  0.983  0.483  0.500  1.0
  O  O16  1  0.532  0.468  0.500  1.0
  O  O17  1  0.968  0.032  0.500  1.0
  O  O18  1  0.532  0.032  0.064  1.0
  O  O19  1  0.968  0.468  0.936  1.0
  O  O20  1  0.000  0.000  0.000  1.0
  O  O21  1  0.750  0.250  0.500  1.0
[/CIF]
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The material described by H2W2O7 crystallizes in the tetragonal I4_1/amd space group. W(1) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms. H(1) is bonded in a single-bond geometry to one O(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent W(1) and one H(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to two equivalent W(1) atoms. In the third O site, O(3) is bonded to four equivalent W(1) atoms to form corner-sharing OW4 tetrahedra. is represented by the CIF card [CIF]
data_H2W2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.063
_cell_length_b   7.063
_cell_length_c   7.063
_cell_angle_alpha   118.123
_cell_angle_beta   118.123
_cell_angle_gamma   93.283
_symmetry_Int_Tables_number   1
_cell_volume   255.794
_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
  H  H0  1  0.334  0.334  0.000  1.0
  H  H1  1  0.666  0.666  0.000  1.0
  H  H2  1  0.416  0.916  0.500  1.0
  H  H3  1  0.084  0.584  0.500  1.0
  W  W4  1  0.875  0.125  0.250  1.0
  W  W5  1  0.875  0.625  0.750  1.0
  W  W6  1  0.875  0.125  0.750  1.0
  W  W7  1  0.375  0.125  0.250  1.0
  O  O8  1  0.233  0.233  0.000  1.0
  O  O9  1  0.767  0.767  0.000  1.0
  O  O10  1  0.218  0.782  0.000  1.0
  O  O11  1  0.782  0.218  0.000  1.0
  O  O12  1  0.218  0.218  0.436  1.0
  O  O13  1  0.782  0.782  0.564  1.0
  O  O14  1  0.517  0.017  0.500  1.0
  O  O15  1  0.983  0.483  0.500  1.0
  O  O16  1  0.532  0.468  0.500  1.0
  O  O17  1  0.968  0.032  0.500  1.0
  O  O18  1  0.532  0.032  0.064  1.0
  O  O19  1  0.968  0.468  0.936  1.0
  O  O20  1  0.000  0.000  0.000  1.0
  O  O21  1  0.750  0.250  0.500  1.0
[/CIF]
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