The crystal structure described by BaCu2(AsO4)2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms to form distorted BaO8 hexagonal bipyramids that share corners with four equivalent As(1)O4 tetrahedra, corners with four equivalent Cu(1)O5 trigonal bipyramids, edges with two equivalent Ba(1)O8 hexagonal bipyramids, edges with two equivalent As(1)O4 tetrahedra, and edges with two equivalent Cu(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form CuO5 trigonal bipyramids that share corners with two equivalent Ba(1)O8 hexagonal bipyramids, corners with five equivalent As(1)O4 tetrahedra,  an edgeedge with one Ba(1)O8 hexagonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. 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 corners with two equivalent Ba(1)O8 hexagonal bipyramids, corners with five equivalent Cu(1)O5 trigonal bipyramids, and  an edgeedge with one Ba(1)O8 hexagonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Cu(1), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Cu(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Cu(1), and one As(1) atom. is represented by the CIF file [CIF]
data_BaCu2(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.877
_cell_length_b   4.763
_cell_length_c   10.052
_cell_angle_alpha   64.195
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   382.637
_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
  Ba  Ba0  1  0.500  0.000  0.500  1.0
  Ba  Ba1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.418  0.895  0.152  1.0
  Cu  Cu3  1  0.582  0.105  0.848  1.0
  Cu  Cu4  1  0.082  0.895  0.652  1.0
  Cu  Cu5  1  0.918  0.105  0.348  1.0
  As  As6  1  0.816  0.373  0.578  1.0
  As  As7  1  0.316  0.627  0.922  1.0
  As  As8  1  0.184  0.627  0.422  1.0
  As  As9  1  0.684  0.373  0.078  1.0
  O  O10  1  0.401  0.274  0.962  1.0
  O  O11  1  0.901  0.726  0.538  1.0
  O  O12  1  0.599  0.726  0.038  1.0
  O  O13  1  0.099  0.274  0.462  1.0
  O  O14  1  0.416  0.917  0.781  1.0
  O  O15  1  0.916  0.083  0.719  1.0
  O  O16  1  0.584  0.083  0.219  1.0
  O  O17  1  0.084  0.917  0.281  1.0
  O  O18  1  0.275  0.687  0.076  1.0
  O  O19  1  0.775  0.313  0.424  1.0
  O  O20  1  0.132  0.615  0.862  1.0
  O  O21  1  0.632  0.385  0.638  1.0
  O  O22  1  0.868  0.385  0.138  1.0
  O  O23  1  0.368  0.615  0.362  1.0
  O  O24  1  0.225  0.687  0.576  1.0
  O  O25  1  0.725  0.313  0.924  1.0
[/CIF]
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The crystal structure described by BaCu2(AsO4)2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms to form distorted BaO8 hexagonal bipyramids that share corners with four equivalent As(1)O4 tetrahedra, corners with four equivalent Cu(1)O5 trigonal bipyramids, edges with two equivalent Ba(1)O8 hexagonal bipyramids, edges with two equivalent As(1)O4 tetrahedra, and edges with two equivalent Cu(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form CuO5 trigonal bipyramids that share corners with two equivalent Ba(1)O8 hexagonal bipyramids, corners with five equivalent As(1)O4 tetrahedra,  an edgeedge with one Ba(1)O8 hexagonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. 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 corners with two equivalent Ba(1)O8 hexagonal bipyramids, corners with five equivalent Cu(1)O5 trigonal bipyramids, and  an edgeedge with one Ba(1)O8 hexagonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Cu(1) and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Cu(1), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Cu(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Cu(1), and one As(1) atom. is represented by the CIF file [CIF]
data_BaCu2(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.877
_cell_length_b   4.763
_cell_length_c   10.052
_cell_angle_alpha   64.195
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   382.637
_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
  Ba  Ba0  1  0.500  0.000  0.500  1.0
  Ba  Ba1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.418  0.895  0.152  1.0
  Cu  Cu3  1  0.582  0.105  0.848  1.0
  Cu  Cu4  1  0.082  0.895  0.652  1.0
  Cu  Cu5  1  0.918  0.105  0.348  1.0
  As  As6  1  0.816  0.373  0.578  1.0
  As  As7  1  0.316  0.627  0.922  1.0
  As  As8  1  0.184  0.627  0.422  1.0
  As  As9  1  0.684  0.373  0.078  1.0
  O  O10  1  0.401  0.274  0.962  1.0
  O  O11  1  0.901  0.726  0.538  1.0
  O  O12  1  0.599  0.726  0.038  1.0
  O  O13  1  0.099  0.274  0.462  1.0
  O  O14  1  0.416  0.917  0.781  1.0
  O  O15  1  0.916  0.083  0.719  1.0
  O  O16  1  0.584  0.083  0.219  1.0
  O  O17  1  0.084  0.917  0.281  1.0
  O  O18  1  0.275  0.687  0.076  1.0
  O  O19  1  0.775  0.313  0.424  1.0
  O  O20  1  0.132  0.615  0.862  1.0
  O  O21  1  0.632  0.385  0.638  1.0
  O  O22  1  0.868  0.385  0.138  1.0
  O  O23  1  0.368  0.615  0.362  1.0
  O  O24  1  0.225  0.687  0.576  1.0
  O  O25  1  0.725  0.313  0.924  1.0
[/CIF]
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