data_[Sr2Er2Cu2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sr  0.9500  2.0000  1.3200
  Er  1.2400  1.7500  1.0300
  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 [8.5028]
_cell_length_b [4.0640]
_cell_length_c [9.0500]
_cell_angle_alpha [90.0000]
_cell_angle_beta [104.2414]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [SrErCuSe3]
_chemical_formula_sum '[Sr2 Er2 Cu2 Se6]'
_cell_volume [303.1214]
_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
[
  Sr  Sr0  2  0.1906  0.2500  0.2428  1.0
  Er  Er1  2  0.3247  0.7500  0.8344  1.0
  Cu  Cu2  2  0.0799  0.2500  0.5838  1.0
  Se  Se3  2  0.1017  0.2500  0.8637  1.0
  Se  Se4  2  0.2253  0.7500  0.5163  1.0
  Se  Se5  2  0.4394  0.7500  0.1629  1.0
]