data_ZnCu2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.74
_cell_length_b   2.74
_cell_length_c   7.64
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   91.49
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZnCu2As
_chemical_formula_sum   'Zn1 Cu2 As1'
_cell_volume   57.54
_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
  Zn  Zn3  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.92  0.0  0.87  1.0
  Cu  Cu2  1  0.92  0.0  0.77  1.0
  As  As0  1  0.0  0.0  0.82  1.0

data_ZnCu2As
_symmetry_space_group_name_H-M   Pm
_cell_length_a   2.74
_cell_length_b   2.74
_cell_length_c   7.64
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   ZnCu2As
_chemical_formula_sum   'Zn1 Cu2 As1'
_cell_volume   57.56
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '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
  Zn  Zn0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.92  0.0  0.77  1.0
  Cu  Cu2  1  0.92  0.0  0.87  1.0
  As  As3  1  0.0  0.0  0.82  1.0

Zn Cu Cu As
Zn Cu Cu As 0 1 - o - 1 3 + o o 2 3 + o o 