data_[Mg8Zn4Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Zn  1.6500  1.3500  0.8800
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/c]
_cell_length_a [12.7175]
_cell_length_b [5.7110]
_cell_length_c [8.8201]
_cell_angle_alpha [90.0000]
_cell_angle_beta [132.0156]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [15]
_chemical_formula_structural [Mg2ZnSe2]
_chemical_formula_sum '[Mg8 Zn4 Se8]'
_cell_volume [475.9445]
_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
[
  Mg  Mg0  8  0.0984  0.2630  0.4850  1
  Zn  Zn1  4  0.0000  0.1687  0.7500  1
  Se  Se2  8  0.1596  0.4744  0.2813  1
]