data_Cu2NiAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.47
_cell_length_b   4.47
_cell_length_c   2.8
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   113.64
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu2NiAs
_chemical_formula_sum   'Cu2 Ni1 As1'
_cell_volume   51.27
_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
  Cu  Cu1  1  0.22  0.13  0.4  1.0
  Cu  Cu2  1  0.22  0.87  0.4  1.0
  Ni  Ni3  1  0.0  0.0  0.0  1.0
  As  As0  1  0.45  0.0  0.0  1.0

data_Cu2NiAs
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.8
_cell_length_b   4.47
_cell_length_c   4.47
_cell_angle_alpha   113.64
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu2NiAs
_chemical_formula_sum   'Cu2 Ni1 As1'
_cell_volume   51.27
_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
  Cu  Cu0  1  0.4  0.22  0.13  1.0
  Cu  Cu1  1  0.4  0.22  0.87  1.0
  Ni  Ni2  1  0.0  0.0  0.0  1.0
  As  As3  1  0.0  0.45  0.0  1.0

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