data_[Na4Sm2Cu4Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Sm  1.1700  1.8500  1.2290
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [14.7726]
_cell_length_b [3.9478]
_cell_length_c [7.6441]
_cell_angle_alpha [90.0000]
_cell_angle_beta [113.0593]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na2Sm(CuSe2)2]
_chemical_formula_sum '[Na4 Sm2 Cu4 Se8]'
_cell_volume [410.1778]
_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  4  0.1254  0.0000  0.0660  1.0
  Sm  Sm1  2  0.0000  0.0000  0.5000  1.0
  Cu  Cu2  4  0.1843  0.5000  0.4926  1.0
  Se  Se3  4  0.0168  0.5000  0.2424  1.0
  Se  Se4  4  0.2150  0.0000  0.7016  1.0
]