data_[K2Er2Se2O2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Er  1.2400  1.7500  1.0300
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pmc2_1]
_cell_length_a [4.5084]
_cell_length_b [8.1388]
_cell_length_c [6.5215]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [26]
_chemical_formula_structural [KErSeO]
_chemical_formula_sum '[K2 Er2 Se2 O2]'
_cell_volume [239.2925]
_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
[
  K  K0  2  0.5000  0.2957  0.1154  1
  Er  Er1  2  0.0000  0.1206  0.5346  1
  Se  Se2  2  0.5000  0.2981  0.6251  1
  O  O3  2  0.0000  0.0897  0.2159  1
]