data_Co2CuAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.13
_cell_length_b   3.13
_cell_length_c   5.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Co2CuAs
_chemical_formula_sum   'Co2 Cu1 As1'
_cell_volume   50.56
_cell_formula_units_Z   1
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
  Co  Co1  1  0.0  0.0  0.03  1.0
  Co  Co2  1  0.56  0.56  0.25  1.0
  Cu  Cu3  1  0.0  0.0  0.52  1.0
  As  As0  1  0.56  0.56  0.96  1.0

data_Co2CuAs
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.42
_cell_length_b   4.42
_cell_length_c   5.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Co2CuAs
_chemical_formula_sum   'Co4 Cu2 As2'
_cell_volume   101.12
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Co  Co0  2  0.0  0.0  0.03  1.0
  Co  Co1  2  0.06  0.5  0.25  1.0
  Cu  Cu2  2  0.0  0.0  0.52  1.0
  As  As3  2  0.06  0.5  0.96  1.0

Co Co Cu As
Co2CuAs crystallizes in the monoclinic Cm space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 4-coordinate geometry to two equivalent Cu(1) and four equivalent As(1) atoms. There is one shorter (2.51 Å) and one longer (2.67 Å) Co(1)-Cu(1) bond length. There are a spread of Co(1)-As(1) bond distances ranging from 1.97-2.52 Å. In the second Co site, Co(2) is bonded in a single-bond geometry to four equivalent Cu(1) and one As(1) atom. There are a spread of Co(2)-Cu(1) bond distances ranging from 2.39-2.85 Å. The Co(2)-As(1) bond length is 1.48 Å. Cu(1) is bonded in a 7-coordinate geometry to two equivalent Co(1), four equivalent Co(2), and one As(1) atom. The Cu(1)-As(1) bond length is 3.00 Å. As(1) is bonded in a 1-coordinate geometry to one Co(2), four equivalent Co(1), and one Cu(1) atom.