The material 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 to six equivalent Cu(3) and six equivalent As(1) atoms to form CuCu6As6 cuboctahedra that share edges with six equivalent Cu(2)Cu9As3 cuboctahedra, faces with two equivalent Cu(1)Cu6As6 cuboctahedra, and faces with six equivalent Cu(2)Cu9As3 cuboctahedra. In the second Cu site, Cu(2) is bonded to nine equivalent Cu(3) and three equivalent As(1) atoms to form distorted CuCu9As3 cuboctahedra that share edges with three equivalent Cu(1)Cu6As6 cuboctahedra, edges with three equivalent Cu(2)Cu9As3 cuboctahedra, faces with three equivalent Cu(1)Cu6As6 cuboctahedra, and faces with five equivalent Cu(2)Cu9As3 cuboctahedra. 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 12-coordinate geometry to two equivalent Cu(1), two equivalent Cu(2), and eight equivalent Cu(3) atoms. is represented by the CIF card [CIF]
data_Cu3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.031
_cell_length_b   7.031
_cell_length_c   7.573
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   324.230
_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  0.000  1.0
  Cu  Cu1  1  0.000  0.000  0.500  1.0
  Cu  Cu2  1  0.333  0.667  0.160  1.0
  Cu  Cu3  1  0.667  0.333  0.340  1.0
  Cu  Cu4  1  0.667  0.333  0.840  1.0
  Cu  Cu5  1  0.333  0.667  0.660  1.0
  Cu  Cu6  1  0.671  0.064  0.083  1.0
  Cu  Cu7  1  0.936  0.608  0.083  1.0
  Cu  Cu8  1  0.392  0.329  0.083  1.0
  Cu  Cu9  1  0.608  0.936  0.417  1.0
  Cu  Cu10  1  0.329  0.392  0.417  1.0
  Cu  Cu11  1  0.064  0.671  0.417  1.0
  Cu  Cu12  1  0.329  0.936  0.917  1.0
  Cu  Cu13  1  0.064  0.392  0.917  1.0
  Cu  Cu14  1  0.608  0.671  0.917  1.0
  Cu  Cu15  1  0.392  0.064  0.583  1.0
  Cu  Cu16  1  0.671  0.608  0.583  1.0
  Cu  Cu17  1  0.936  0.329  0.583  1.0
  As  As18  1  0.303  0.000  0.250  1.0
  As  As19  1  0.000  0.303  0.250  1.0
  As  As20  1  0.697  0.697  0.250  1.0
  As  As21  1  0.697  0.000  0.750  1.0
  As  As22  1  0.000  0.697  0.750  1.0
  As  As23  1  0.303  0.303  0.750  1.0
[/CIF]
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The material 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 to six equivalent Cu(3) and six equivalent As(1) atoms to form CuCu6As6 cuboctahedra that share edges with six equivalent Cu(2)Cu9As3 cuboctahedra, faces with two equivalent Cu(1)Cu6As6 cuboctahedra, and faces with six equivalent Cu(2)Cu9As3 cuboctahedra. In the second Cu site, Cu(2) is bonded to nine equivalent Cu(3) and three equivalent As(1) atoms to form distorted CuCu9As3 cuboctahedra that share edges with three equivalent Cu(1)Cu6As6 cuboctahedra, edges with three equivalent Cu(2)Cu9As3 cuboctahedra, faces with three equivalent Cu(1)Cu6As6 cuboctahedra, and faces with five equivalent Cu(2)Cu9As3 cuboctahedra. 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 12-coordinate geometry to two equivalent Cu(1), two equivalent Cu(2), and eight equivalent Cu(3) atoms. is represented by the CIF card [CIF]
data_Cu3As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.031
_cell_length_b   7.031
_cell_length_c   7.573
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   324.230
_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  0.000  1.0
  Cu  Cu1  1  0.000  0.000  0.500  1.0
  Cu  Cu2  1  0.333  0.667  0.160  1.0
  Cu  Cu3  1  0.667  0.333  0.340  1.0
  Cu  Cu4  1  0.667  0.333  0.840  1.0
  Cu  Cu5  1  0.333  0.667  0.660  1.0
  Cu  Cu6  1  0.671  0.064  0.083  1.0
  Cu  Cu7  1  0.936  0.608  0.083  1.0
  Cu  Cu8  1  0.392  0.329  0.083  1.0
  Cu  Cu9  1  0.608  0.936  0.417  1.0
  Cu  Cu10  1  0.329  0.392  0.417  1.0
  Cu  Cu11  1  0.064  0.671  0.417  1.0
  Cu  Cu12  1  0.329  0.936  0.917  1.0
  Cu  Cu13  1  0.064  0.392  0.917  1.0
  Cu  Cu14  1  0.608  0.671  0.917  1.0
  Cu  Cu15  1  0.392  0.064  0.583  1.0
  Cu  Cu16  1  0.671  0.608  0.583  1.0
  Cu  Cu17  1  0.936  0.329  0.583  1.0
  As  As18  1  0.303  0.000  0.250  1.0
  As  As19  1  0.000  0.303  0.250  1.0
  As  As20  1  0.697  0.697  0.250  1.0
  As  As21  1  0.697  0.000  0.750  1.0
  As  As22  1  0.000  0.697  0.750  1.0
  As  As23  1  0.303  0.303  0.750  1.0
[/CIF]
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