data_[Nd6Cu18Se18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Nd  1.1400  1.8500  1.2765
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [7.0567]
_cell_length_b [7.0567]
_cell_length_c [20.1801]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Nd(CuSe)3]
_chemical_formula_sum '[Nd6 Cu18 Se18]'
_cell_volume [870.2876]
_cell_formula_units_Z [6]
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
[
  Nd  Nd0  6  0.0000  0.0000  0.3337  1.0
  Cu  Cu1  18  0.0045  0.3571  0.1238  1.0
  Se  Se2  18  0.0016  0.3193  0.9149  1.0
]