data_[Gd2Er2Si4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Gd  1.2000  1.8000  1.0750
  Er  1.2400  1.7500  1.0300
  Si  1.9000  1.1000  0.5400
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [5.6997]
_cell_length_b [3.8346]
_cell_length_c [7.9142]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.2662]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [GdErSi2]
_chemical_formula_sum '[Gd2 Er2 Si4]'
_cell_volume [172.9715]
_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
[
  Gd  Gd0  2  0.3853  0.2500  0.3203  1
  Er  Er1  2  0.1149  0.2500  0.8212  1
  Si  Si2  2  0.1277  0.7500  0.5390  1
  Si  Si3  2  0.3698  0.7500  0.0369  1
]