data_NaCu2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.63
_cell_length_b   5.63
_cell_length_c   7.3
_cell_angle_alpha   110.4
_cell_angle_beta   110.4
_cell_angle_gamma   27.43
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaCu2
_chemical_formula_sum   'Na2 Cu4'
_cell_volume   99.52
_cell_formula_units_Z   2
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
  Na  Na4  1  0.54  0.0  0.21  1.0
  Na  Na5  1  0.78  0.0  0.6  1.0
  Cu  Cu0  1  0.18  0.0  0.7  1.0
  Cu  Cu1  1  0.92  0.0  0.34  1.0
  Cu  Cu2  1  0.4  0.0  0.47  1.0
  Cu  Cu3  1  0.15  0.0  0.11  1.0

data_NaCu2
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.67
_cell_length_b   5.63
_cell_length_c   7.3
_cell_angle_alpha   110.4
_cell_angle_beta   90.0
_cell_angle_gamma   103.71
_symmetry_Int_Tables_number   2
_chemical_formula_structural   NaCu2
_chemical_formula_sum   'Na2 Cu4'
_cell_volume   99.52
_cell_formula_units_Z   2
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
  Na  Na0  2  0.0  0.12  0.7  1.0
  Cu  Cu1  2  0.0  0.26  0.43  1.0
  Cu  Cu2  2  0.0  0.49  0.21  1.0

Na Na Cu Cu Cu Cu