data_NbCu3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.23
_cell_length_b   5.23
_cell_length_c   5.23
_cell_angle_alpha   150.62
_cell_angle_beta   60.84
_cell_angle_gamma   128.01
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCu3
_chemical_formula_sum   'Nb1 Cu3'
_cell_volume   54.69
_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  0.32  0.0  0.79  1.0
  Cu  Cu0  1  0.32  0.11  0.75  1.0
  Cu  Cu1  1  0.0  0.39  0.04  1.0
  Cu  Cu2  1  0.0  0.0  0.05  1.0

data_NbCu3
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.65
_cell_length_b   4.58
_cell_length_c   5.23
_cell_angle_alpha   115.99
_cell_angle_beta   104.69
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbCu3
_chemical_formula_sum   'Nb1 Cu3'
_cell_volume   54.69
_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  0.68  0.21  0.89  1.0
  Cu  Cu1  1  -0.0  0.95  0.95  1.0
  Cu  Cu2  1  0.39  0.35  0.35  1.0
  Cu  Cu3  1  0.79  0.36  0.03  1.0

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