data_[Er4Cu4Se4O4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2_1]
_cell_length_a [5.6139]
_cell_length_b [5.6203]
_cell_length_c [10.8164]
_cell_angle_alpha [90.0000]
_cell_angle_beta [92.2857]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [4]
_chemical_formula_structural [ErCuSeO]
_chemical_formula_sum '[Er4 Cu4 Se4 O4]'
_cell_volume [341.0080]
_cell_formula_units_Z [4]
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  0.0065  0.8199  0.5967  1
  Er  Er1  2  0.4945  0.8196  0.4048  1
  Cu  Cu2  2  0.0029  0.8424  0.2183  1
  Cu  Cu3  2  0.3093  0.0957  0.0037  1
  Se  Se4  2  0.2828  0.0621  0.7942  1
  Se  Se5  2  0.2883  0.1239  0.2120  1
  O  O6  2  0.2482  0.0677  0.5012  1
  O  O7  2  0.2503  0.5688  0.4997  1
]