The material structure described by Cu2As2O7 crystallizes in the monoclinic C2/c space group. Cu(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with five equivalent As(1)O4 tetrahedra and edges with two equivalent Cu(1)O5 trigonal bipyramids. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 tetrahedra that share  a cornercorner with one As(1)O4 tetrahedra and corners with five equivalent Cu(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cu(1) and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Cu2As2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.504
_cell_length_b   5.504
_cell_length_c   9.867
_cell_angle_alpha   75.681
_cell_angle_beta   75.681
_cell_angle_gamma   96.545
_symmetry_Int_Tables_number   1
_cell_volume   275.718
_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
  Cu  Cu0  1  0.725  0.859  0.990  1.0
  Cu  Cu1  1  0.141  0.275  0.510  1.0
  Cu  Cu2  1  0.275  0.141  0.010  1.0
  Cu  Cu3  1  0.859  0.725  0.490  1.0
  As  As4  1  0.505  0.978  0.705  1.0
  As  As5  1  0.495  0.022  0.295  1.0
  As  As6  1  0.022  0.495  0.795  1.0
  As  As7  1  0.978  0.505  0.205  1.0
  O  O8  1  0.478  0.975  0.133  1.0
  O  O9  1  0.791  0.609  0.888  1.0
  O  O10  1  0.522  0.025  0.867  1.0
  O  O11  1  0.975  0.478  0.633  1.0
  O  O12  1  0.204  0.046  0.391  1.0
  O  O13  1  0.609  0.791  0.388  1.0
  O  O14  1  0.391  0.209  0.612  1.0
  O  O15  1  0.669  0.331  0.250  1.0
  O  O16  1  0.954  0.796  0.109  1.0
  O  O17  1  0.796  0.954  0.609  1.0
  O  O18  1  0.025  0.522  0.367  1.0
  O  O19  1  0.209  0.391  0.112  1.0
  O  O20  1  0.331  0.669  0.750  1.0
  O  O21  1  0.046  0.204  0.891  1.0
[/CIF]
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The material structure described by Cu2As2O7 crystallizes in the monoclinic C2/c space group. Cu(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted CuO5 trigonal bipyramids that share corners with five equivalent As(1)O4 tetrahedra and edges with two equivalent Cu(1)O5 trigonal bipyramids. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 tetrahedra that share  a cornercorner with one As(1)O4 tetrahedra and corners with five equivalent Cu(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cu(1) and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent As(1) atoms. is represented by the CIF card [CIF]
data_Cu2As2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.504
_cell_length_b   5.504
_cell_length_c   9.867
_cell_angle_alpha   75.681
_cell_angle_beta   75.681
_cell_angle_gamma   96.545
_symmetry_Int_Tables_number   1
_cell_volume   275.718
_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
  Cu  Cu0  1  0.725  0.859  0.990  1.0
  Cu  Cu1  1  0.141  0.275  0.510  1.0
  Cu  Cu2  1  0.275  0.141  0.010  1.0
  Cu  Cu3  1  0.859  0.725  0.490  1.0
  As  As4  1  0.505  0.978  0.705  1.0
  As  As5  1  0.495  0.022  0.295  1.0
  As  As6  1  0.022  0.495  0.795  1.0
  As  As7  1  0.978  0.505  0.205  1.0
  O  O8  1  0.478  0.975  0.133  1.0
  O  O9  1  0.791  0.609  0.888  1.0
  O  O10  1  0.522  0.025  0.867  1.0
  O  O11  1  0.975  0.478  0.633  1.0
  O  O12  1  0.204  0.046  0.391  1.0
  O  O13  1  0.609  0.791  0.388  1.0
  O  O14  1  0.391  0.209  0.612  1.0
  O  O15  1  0.669  0.331  0.250  1.0
  O  O16  1  0.954  0.796  0.109  1.0
  O  O17  1  0.796  0.954  0.609  1.0
  O  O18  1  0.025  0.522  0.367  1.0
  O  O19  1  0.209  0.391  0.112  1.0
  O  O20  1  0.331  0.669  0.750  1.0
  O  O21  1  0.046  0.204  0.891  1.0
[/CIF]
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