data_[Rb8Mg4O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Mg  1.3100  1.5000  0.8600
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pbcn]
_cell_length_a [10.9318]
_cell_length_b [6.5283]
_cell_length_c [5.6365]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [60]
_chemical_formula_structural [Rb2MgO2]
_chemical_formula_sum '[Rb8 Mg4 O8]'
_cell_volume [402.2530]
_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
[
  Rb  Rb0  8  0.1556  0.3623  0.5617  1.0
  Mg  Mg1  4  0.0000  0.0128  0.2500  1.0
  O  O2  8  0.0907  0.1655  0.9943  1.0
]