data_[Tm8Si4O2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Tm  1.2500  1.7500  1.0950
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [I4/mmm]
_cell_length_a [4.3937]
_cell_length_b [4.3937]
_cell_length_c [15.3746]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [139]
_chemical_formula_structural [Tm4Si2O]
_chemical_formula_sum '[Tm8 Si4 O2]'
_cell_volume [296.8011]
_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
[
  Tm  Tm0  4  0.0000  0.0000  0.1773  1
  Tm  Tm1  4  0.0000  0.5000  0.0000  1
  Si  Si2  4  0.0000  0.0000  0.3643  1
  O  O3  2  0.0000  0.0000  0.0000  1
]