The compound described by Zn2As2O7 crystallizes in the monoclinic C2/m space group. Zn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted ZnO6 pentagonal pyramids that share corners with six equivalent As(1)O4 tetrahedra and edges with three equivalent Zn(1)O6 pentagonal pyramids. As(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form AsO4 tetrahedra that share corners with six equivalent Zn(1)O6 pentagonal pyramids and  a cornercorner with one As(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one As(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one As(1) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Zn2As2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.481
_cell_length_b   5.481
_cell_length_c   4.863
_cell_angle_alpha   81.147
_cell_angle_beta   81.147
_cell_angle_gamma   103.857
_symmetry_Int_Tables_number   1
_cell_volume   137.356
_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
  Zn  Zn0  1  0.307  0.693  0.000  1.0
  Zn  Zn1  1  0.693  0.307  0.000  1.0
  As  As2  1  0.769  0.769  0.402  1.0
  As  As3  1  0.231  0.231  0.598  1.0
  O  O4  1  0.406  0.406  0.273  1.0
  O  O5  1  0.602  0.934  0.210  1.0
  O  O6  1  0.934  0.602  0.210  1.0
  O  O7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.066  0.398  0.790  1.0
  O  O9  1  0.398  0.066  0.790  1.0
  O  O10  1  0.594  0.594  0.727  1.0
[/CIF]
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The compound described by Zn2As2O7 crystallizes in the monoclinic C2/m space group. Zn(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted ZnO6 pentagonal pyramids that share corners with six equivalent As(1)O4 tetrahedra and edges with three equivalent Zn(1)O6 pentagonal pyramids. As(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form AsO4 tetrahedra that share corners with six equivalent Zn(1)O6 pentagonal pyramids and  a cornercorner with one As(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one As(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Zn(1) and one As(1) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Zn2As2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.481
_cell_length_b   5.481
_cell_length_c   4.863
_cell_angle_alpha   81.147
_cell_angle_beta   81.147
_cell_angle_gamma   103.857
_symmetry_Int_Tables_number   1
_cell_volume   137.356
_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
  Zn  Zn0  1  0.307  0.693  0.000  1.0
  Zn  Zn1  1  0.693  0.307  0.000  1.0
  As  As2  1  0.769  0.769  0.402  1.0
  As  As3  1  0.231  0.231  0.598  1.0
  O  O4  1  0.406  0.406  0.273  1.0
  O  O5  1  0.602  0.934  0.210  1.0
  O  O6  1  0.934  0.602  0.210  1.0
  O  O7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.066  0.398  0.790  1.0
  O  O9  1  0.398  0.066  0.790  1.0
  O  O10  1  0.594  0.594  0.727  1.0
[/CIF]
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