data_[Rb4Be4Tl8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Be  1.5700  1.0500  0.5900
  Tl  1.6200  1.9000  1.3325
]
_symmetry_space_group_name_H-M [I4_1/amd]
_cell_length_a [6.8357]
_cell_length_b [6.8357]
_cell_length_c [13.4555]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [141]
_chemical_formula_structural [RbBeTl2]
_chemical_formula_sum '[Rb4 Be4 Tl8]'
_cell_volume [628.7268]
_cell_formula_units_Z [4]
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
[
  Rb  Rb0  4  0.0000  0.0000  0.0000  1
  Be  Be1  4  0.0000  0.0000  0.5000  1
  Tl  Tl2  8  0.0000  0.2500  0.6250  1
]