data_[Er2Mg2Cu2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Mg  1.3100  1.5000  0.8600
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [7.8338]
_cell_length_b [3.8605]
_cell_length_c [8.7515]
_cell_angle_alpha [90.0000]
_cell_angle_beta [101.7423]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [ErMgCuSe3]
_chemical_formula_sum '[Er2 Mg2 Cu2 Se6]'
_cell_volume [259.1287]
_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  0.1834  0.2500  0.2494  1.0
  Mg  Mg1  2  0.3382  0.7500  0.8378  1.0
  Cu  Cu2  2  0.0779  0.2500  0.5792  1.0
  Se  Se3  2  0.0886  0.2500  0.8627  1.0
  Se  Se4  2  0.2547  0.7500  0.5115  1.0
  Se  Se5  2  0.4131  0.7500  0.1519  1.0
]