data_[Rb4Be2Nb2I12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Be  1.5700  1.0500  0.5900
  Nb  1.6000  1.4500  0.8200
  I  2.6600  1.4000  1.2733
]
_symmetry_space_group_name_H-M [I4/mmm]
_cell_length_a [8.7341]
_cell_length_b [8.7341]
_cell_length_c [10.6308]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [139]
_chemical_formula_structural [Rb2BeNbI6]
_chemical_formula_sum '[Rb4 Be2 Nb2 I12]'
_cell_volume [810.9727]
_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
[
  Rb  Rb0  4  0.0000  0.5000  0.2500  1
  Be  Be1  2  0.0000  0.0000  0.5000  1
  Nb  Nb2  2  0.0000  0.0000  0.0000  1
  I  I3  8  0.2342  0.2342  0.0000  1
  I  I4  4  0.0000  0.0000  0.2835  1
]