data_[Be8Cu4Se12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Be  1.5700  1.0500  0.5900
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Amm2]
_cell_length_a [19.8422]
_cell_length_b [3.6963]
_cell_length_c [21.2222]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [38]
_chemical_formula_structural [Be2CuSe3]
_chemical_formula_sum '[Be8 Cu4 Se12]'
_cell_volume [1556.5025]
_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  0.0627  0.0000  0.6940  1
  Be  Be1  4  0.1122  0.0000  0.1286  1
  Cu  Cu2  2  0.0000  0.0000  0.2454  1
  Cu  Cu3  2  0.0000  0.0000  0.5074  1
  Se  Se4  4  0.0951  0.0000  0.5812  1
  Se  Se5  4  0.1220  0.0000  0.2282  1
  Se  Se6  2  0.0000  0.0000  0.8286  1
  Se  Se7  2  0.0000  0.0000  0.9407  1
]