data_[Er2Tl2Si2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Tl  1.6200  1.9000  1.3325
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [5.6686]
_cell_length_b [5.6685]
_cell_length_c [7.7776]
_cell_angle_alpha [90.0000]
_cell_angle_beta [106.5163]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [ErTlSiO4]
_chemical_formula_sum '[Er2 Tl2 Si2 O8]'
_cell_volume [239.6050]
_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
[
  Er  Er0  2  0.2125  0.7500  0.5505  1.0
  Tl  Tl1  2  0.3206  0.7500  0.1028  1.0
  Si  Si2  2  0.2560  0.2500  0.3556  1.0
  O  O3  4  0.0642  0.0247  0.3398  1.0
  O  O4  2  0.4331  0.2500  0.2222  1.0
  O  O5  2  0.4509  0.2500  0.5590  1.0
]