data_[Mn4Cu4Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mn  1.5500  1.4000  0.6483
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pna2_1]
_cell_length_a [6.6686]
_cell_length_b [7.5507]
_cell_length_c [6.3797]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [33]
_chemical_formula_structural [MnCuSe2]
_chemical_formula_sum '[Mn4 Cu4 Se8]'
_cell_volume [321.2370]
_cell_formula_units_Z [4]
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
[
  Mn  Mn0  4  0.0645  0.8788  0.0020  1
  Cu  Cu1  4  0.0937  0.3925  0.9913  1
  Se  Se2  4  0.0728  0.8691  0.6422  1
  Se  Se3  4  0.1094  0.3650  0.6143  1
]