data_[Be4Cu4Se4O4]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pca2_1]
_cell_length_a [5.7413]
_cell_length_b [6.6598]
_cell_length_c [5.6998]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [29]
_chemical_formula_structural [BeCuSeO]
_chemical_formula_sum '[Be4 Cu4 Se4 O4]'
_cell_volume [217.9358]
_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  0.0424  0.3250  0.5350  1
  Cu  Cu1  4  0.1288  0.8990  0.4549  1
  Se  Se2  4  0.0816  0.3699  0.1439  1
  O  O3  4  0.0694  0.8719  0.1161  1
]