The crystal structure described by Cu2AsO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form CuO5 square pyramids that share corners with four equivalent Cu(2)O6 octahedra, corners with four equivalent As(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 48-57°. In the second Cu site, Cu(2) is bonded to one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form CuO6 octahedra that share corners with four equivalent Cu(1)O5 square pyramids, corners with four equivalent As(1)O4 tetrahedra, and edges with two equivalent Cu(2)O6 octahedra. As(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with four equivalent Cu(2)O6 octahedra and corners with four equivalent Cu(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 55-72°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Cu(2) and one As(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Cu(1) and two equivalent Cu(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one As(1) atom. is represented by the CIF card [CIF]
data_Cu2AsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.771
_cell_length_b   8.029
_cell_length_c   8.554
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.509
_symmetry_Int_Tables_number   1
_cell_volume   396.354
_cell_formula_units_Z   4
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  0.531  0.853  0.609  1.0
  Cu  Cu1  1  0.469  0.147  0.391  1.0
  Cu  Cu2  1  0.031  0.353  0.891  1.0
  Cu  Cu3  1  0.969  0.647  0.109  1.0
  Cu  Cu4  1  0.748  0.500  0.501  1.0
  Cu  Cu5  1  0.252  0.500  0.499  1.0
  Cu  Cu6  1  0.248  1.000  0.999  1.0
  Cu  Cu7  1  0.752  0.000  0.001  1.0
  As  As8  1  0.485  0.759  0.253  1.0
  As  As9  1  0.515  0.241  0.747  1.0
  As  As10  1  0.985  0.259  0.247  1.0
  As  As11  1  0.015  0.741  0.753  1.0
  O  O12  1  0.434  0.906  0.396  1.0
  O  O13  1  0.566  0.094  0.604  1.0
  O  O14  1  0.934  0.406  0.104  1.0
  O  O15  1  0.066  0.594  0.896  1.0
  O  O16  1  0.494  0.862  0.075  1.0
  O  O17  1  0.506  0.138  0.925  1.0
  O  O18  1  0.994  0.362  0.425  1.0
  O  O19  1  0.006  0.638  0.575  1.0
  O  O20  1  0.504  0.631  0.567  1.0
  O  O21  1  0.496  0.369  0.433  1.0
  O  O22  1  0.004  0.131  0.933  1.0
  O  O23  1  0.996  0.869  0.067  1.0
  O  O24  1  0.749  0.669  0.278  1.0
  O  O25  1  0.251  0.331  0.722  1.0
  O  O26  1  0.249  0.169  0.222  1.0
  O  O27  1  0.751  0.831  0.778  1.0
  O  O28  1  0.263  0.624  0.255  1.0
  O  O29  1  0.737  0.376  0.745  1.0
  O  O30  1  0.763  0.124  0.245  1.0
  O  O31  1  0.237  0.876  0.755  1.0
[/CIF]
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The crystal structure described by Cu2AsO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form CuO5 square pyramids that share corners with four equivalent Cu(2)O6 octahedra, corners with four equivalent As(1)O4 tetrahedra, and  an edgeedge with one Cu(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 48-57°. In the second Cu site, Cu(2) is bonded to one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms to form CuO6 octahedra that share corners with four equivalent Cu(1)O5 square pyramids, corners with four equivalent As(1)O4 tetrahedra, and edges with two equivalent Cu(2)O6 octahedra. As(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form AsO4 tetrahedra that share corners with four equivalent Cu(2)O6 octahedra and corners with four equivalent Cu(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 55-72°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Cu(2) and one As(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Cu(1) and two equivalent Cu(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one As(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one As(1) atom. is represented by the CIF card [CIF]
data_Cu2AsO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.771
_cell_length_b   8.029
_cell_length_c   8.554
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.509
_symmetry_Int_Tables_number   1
_cell_volume   396.354
_cell_formula_units_Z   4
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  0.531  0.853  0.609  1.0
  Cu  Cu1  1  0.469  0.147  0.391  1.0
  Cu  Cu2  1  0.031  0.353  0.891  1.0
  Cu  Cu3  1  0.969  0.647  0.109  1.0
  Cu  Cu4  1  0.748  0.500  0.501  1.0
  Cu  Cu5  1  0.252  0.500  0.499  1.0
  Cu  Cu6  1  0.248  1.000  0.999  1.0
  Cu  Cu7  1  0.752  0.000  0.001  1.0
  As  As8  1  0.485  0.759  0.253  1.0
  As  As9  1  0.515  0.241  0.747  1.0
  As  As10  1  0.985  0.259  0.247  1.0
  As  As11  1  0.015  0.741  0.753  1.0
  O  O12  1  0.434  0.906  0.396  1.0
  O  O13  1  0.566  0.094  0.604  1.0
  O  O14  1  0.934  0.406  0.104  1.0
  O  O15  1  0.066  0.594  0.896  1.0
  O  O16  1  0.494  0.862  0.075  1.0
  O  O17  1  0.506  0.138  0.925  1.0
  O  O18  1  0.994  0.362  0.425  1.0
  O  O19  1  0.006  0.638  0.575  1.0
  O  O20  1  0.504  0.631  0.567  1.0
  O  O21  1  0.496  0.369  0.433  1.0
  O  O22  1  0.004  0.131  0.933  1.0
  O  O23  1  0.996  0.869  0.067  1.0
  O  O24  1  0.749  0.669  0.278  1.0
  O  O25  1  0.251  0.331  0.722  1.0
  O  O26  1  0.249  0.169  0.222  1.0
  O  O27  1  0.751  0.831  0.778  1.0
  O  O28  1  0.263  0.624  0.255  1.0
  O  O29  1  0.737  0.376  0.745  1.0
  O  O30  1  0.763  0.124  0.245  1.0
  O  O31  1  0.237  0.876  0.755  1.0
[/CIF]
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