data_[Na4Sm6Cu2Se12]
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 [7.2790]
_cell_length_b [12.6191]
_cell_length_c [7.0931]
_cell_angle_alpha [90.0000]
_cell_angle_beta [109.8345]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na2Sm3CuSe6]
_chemical_formula_sum '[Na4 Sm6 Cu2 Se12]'
_cell_volume [612.8832]
_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  0.0000  0.3337  0.0000  1
  Sm  Sm1  4  0.0000  0.1673  0.5000  1
  Sm  Sm2  2  0.0000  0.5000  0.5000  1
  Cu  Cu3  2  0.0000  0.0000  0.0000  1
  Se  Se4  8  0.2465  0.1620  0.2519  1
  Se  Se5  4  0.2389  0.0000  0.7488  1
]