data_[Cu4Sn2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Cu  1.9000  1.3500  0.8200
  Sn  1.9600  1.4500  0.8300
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Imm2]
_cell_length_a [4.1297]
_cell_length_b [12.2286]
_cell_length_c [5.7158]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [44]
_chemical_formula_structural [Cu2SnSe3]
_chemical_formula_sum '[Cu4 Sn2 Se6]'
_cell_volume [288.6542]
_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
[
  Cu  Cu0  4  0.0000  0.1709  0.7380  1.0
  Sn  Sn1  2  0.0000  0.5000  0.7666  1.0
  Se  Se2  4  0.0000  0.3217  0.0151  1.0
  Se  Se3  2  0.0000  0.0000  0.9653  1.0
]