data_[Tl6Cu18Se18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Tl  1.6200  1.9000  1.3325
  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 [6.8115]
_cell_length_b [6.8115]
_cell_length_c [23.8686]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Tl(CuSe)3]
_chemical_formula_sum '[Tl6 Cu18 Se18]'
_cell_volume [959.0427]
_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
[
  Tl  Tl0  6  0.0000  0.0000  0.3338  1.0
  Cu  Cu1  18  0.0013  0.3371  0.1326  1.0
  Se  Se2  18  0.0010  0.3311  0.9031  1.0
]