data_[Be4Tl4Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Be  1.5700  1.0500  0.5900
  Tl  1.6200  1.9000  1.3325
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Fmm2]
_cell_length_a [3.7017]
_cell_length_b [6.7184]
_cell_length_c [12.6124]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [42]
_chemical_formula_structural [BeTlSe]
_chemical_formula_sum '[Be4 Tl4 Se4]'
_cell_volume [313.6600]
_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
[
  Be  Be0  4  0.0000  0.0000  0.0345  1
  Tl  Tl1  4  0.0000  0.0000  0.3554  1
  Se  Se2  4  0.0000  0.0000  0.6102  1
]