data_[Be4Si4Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Be  1.5700  1.0500  0.5900
  Si  1.9000  1.1000  0.5400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Ama2]
_cell_length_a [3.7379]
_cell_length_b [11.7789]
_cell_length_c [5.5723]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [40]
_chemical_formula_structural [BeSiSe]
_chemical_formula_sum '[Be4 Si4 Se4]'
_cell_volume [245.3347]
_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  0.2500  0.1980  0.9876  1
  Si  Si1  4  0.2500  0.0576  0.7159  1
  Se  Se2  4  0.2500  0.1976  0.3937  1
]