The crystal structure described by Cu3As crystallizes in the trigonal P-3c1 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a trigonal planar geometry to six equivalent Cu(3) and three equivalent As(1) atoms. In the second Cu site, Cu(2) is bonded in a distorted trigonal non-coplanar geometry to nine equivalent Cu(3) and three equivalent As(1) atoms. In the third Cu site, Cu(3) is bonded in a 12-coordinate geometry to one Cu(1), three equivalent Cu(2), four equivalent Cu(3), and four equivalent As(1) atoms. As(1) is bonded in a 9-coordinate geometry to one Cu(1), two equivalent Cu(2), and eight equivalent Cu(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.191
_cell_length_b   7.191
_cell_length_c   7.405
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   331.574
_cell_formula_units_Z   6
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  0.000  0.000  0.750  1.0
  Cu  Cu1  1  0.000  0.000  0.250  1.0
  Cu  Cu2  1  0.333  0.667  0.654  1.0
  Cu  Cu3  1  0.667  0.333  0.846  1.0
  Cu  Cu4  1  0.667  0.333  0.346  1.0
  Cu  Cu5  1  0.333  0.667  0.154  1.0
  Cu  Cu6  1  0.370  0.054  0.081  1.0
  Cu  Cu7  1  0.946  0.316  0.081  1.0
  Cu  Cu8  1  0.684  0.630  0.081  1.0
  Cu  Cu9  1  0.316  0.946  0.419  1.0
  Cu  Cu10  1  0.630  0.684  0.419  1.0
  Cu  Cu11  1  0.054  0.370  0.419  1.0
  Cu  Cu12  1  0.630  0.946  0.919  1.0
  Cu  Cu13  1  0.054  0.684  0.919  1.0
  Cu  Cu14  1  0.316  0.370  0.919  1.0
  Cu  Cu15  1  0.684  0.054  0.581  1.0
  Cu  Cu16  1  0.370  0.316  0.581  1.0
  Cu  Cu17  1  0.946  0.630  0.581  1.0
  As  As18  1  0.663  0.663  0.750  1.0
  As  As19  1  0.000  0.337  0.750  1.0
  As  As20  1  0.337  0.000  0.750  1.0
  As  As21  1  0.337  0.337  0.250  1.0
  As  As22  1  0.000  0.663  0.250  1.0
  As  As23  1  0.663  0.000  0.250  1.0
[/CIF]
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The crystal structure described by Cu3As crystallizes in the trigonal P-3c1 space group. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a trigonal planar geometry to six equivalent Cu(3) and three equivalent As(1) atoms. In the second Cu site, Cu(2) is bonded in a distorted trigonal non-coplanar geometry to nine equivalent Cu(3) and three equivalent As(1) atoms. In the third Cu site, Cu(3) is bonded in a 12-coordinate geometry to one Cu(1), three equivalent Cu(2), four equivalent Cu(3), and four equivalent As(1) atoms. As(1) is bonded in a 9-coordinate geometry to one Cu(1), two equivalent Cu(2), and eight equivalent Cu(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cu3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.191
_cell_length_b   7.191
_cell_length_c   7.405
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   331.574
_cell_formula_units_Z   6
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  0.000  0.000  0.750  1.0
  Cu  Cu1  1  0.000  0.000  0.250  1.0
  Cu  Cu2  1  0.333  0.667  0.654  1.0
  Cu  Cu3  1  0.667  0.333  0.846  1.0
  Cu  Cu4  1  0.667  0.333  0.346  1.0
  Cu  Cu5  1  0.333  0.667  0.154  1.0
  Cu  Cu6  1  0.370  0.054  0.081  1.0
  Cu  Cu7  1  0.946  0.316  0.081  1.0
  Cu  Cu8  1  0.684  0.630  0.081  1.0
  Cu  Cu9  1  0.316  0.946  0.419  1.0
  Cu  Cu10  1  0.630  0.684  0.419  1.0
  Cu  Cu11  1  0.054  0.370  0.419  1.0
  Cu  Cu12  1  0.630  0.946  0.919  1.0
  Cu  Cu13  1  0.054  0.684  0.919  1.0
  Cu  Cu14  1  0.316  0.370  0.919  1.0
  Cu  Cu15  1  0.684  0.054  0.581  1.0
  Cu  Cu16  1  0.370  0.316  0.581  1.0
  Cu  Cu17  1  0.946  0.630  0.581  1.0
  As  As18  1  0.663  0.663  0.750  1.0
  As  As19  1  0.000  0.337  0.750  1.0
  As  As20  1  0.337  0.000  0.750  1.0
  As  As21  1  0.337  0.337  0.250  1.0
  As  As22  1  0.000  0.663  0.250  1.0
  As  As23  1  0.663  0.000  0.250  1.0
[/CIF]
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