data_[Sr4Nb4Se2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sr  0.9500  2.0000  1.3200
  Nb  1.6000  1.4500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [I4/mmm]
_cell_length_a [4.9397]
_cell_length_b [4.9397]
_cell_length_c [13.6551]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [139]
_chemical_formula_structural [Sr2Nb2Se]
_chemical_formula_sum '[Sr4 Nb4 Se2]'
_cell_volume [333.1954]
_cell_formula_units_Z [2]
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
[
  Sr  Sr0  4  0.0000  0.5000  0.2500  1
  Nb  Nb1  4  0.0000  0.0000  0.4233  1
  Se  Se2  2  0.0000  0.0000  0.0000  1
]