data_[Na2Er2Si2S8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Er  1.2400  1.7500  1.0300
  Si  1.9000  1.1000  0.5400
  S  2.5800  1.0000  0.8800
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [6.3562]
_cell_length_b [6.5857]
_cell_length_c [7.9406]
_cell_angle_alpha [90.0000]
_cell_angle_beta [105.8208]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [NaErSiS4]
_chemical_formula_sum '[Na2 Er2 Si2 S8]'
_cell_volume [319.8059]
_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
[
  Na  Na0  2  0.2524  0.2500  0.0627  1.0
  Er  Er1  2  0.2228  0.2500  0.5533  1.0
  Si  Si2  2  0.2388  0.7500  0.3178  1.0
  S  S3  4  0.0123  0.5012  0.2734  1.0
  S  S4  2  0.4258  0.7500  0.5836  1.0
  S  S5  2  0.4422  0.7500  0.1497  1.0
]