data_NbCu2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.95
_cell_length_b   2.95
_cell_length_c   6.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   97.99
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCu2As
_chemical_formula_sum   'Nb1 Cu2 As1'
_cell_volume   59.82
_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
  Nb  Nb3  1  0.94  0.0  0.55  1.0
  Cu  Cu1  1  0.94  0.0  0.81  1.0
  Cu  Cu2  1  0.0  0.0  0.32  1.0
  As  As0  1  0.0  0.0  0.62  1.0

data_NbCu2As
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.95
_cell_length_b   2.95
_cell_length_c   6.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   97.99
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCu2As
_chemical_formula_sum   'Nb1 Cu2 As1'
_cell_volume   59.82
_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
  Nb  Nb0  1  0.94  0.0  0.55  1.0
  Cu  Cu1  1  0.0  0.0  0.32  1.0
  Cu  Cu2  1  0.94  0.0  0.81  1.0
  As  As3  1  0.0  0.0  0.62  1.0

Nb Cu Cu As
Nb Cu Cu As 0 3 + o o 0 2 + o o 1 3 + o o 