data_[Mg4Zn4Se8]
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 [Pna2_1]
_cell_length_a [7.1873]
_cell_length_b [8.3198]
_cell_length_c [6.7763]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [33]
_chemical_formula_structural [MgZnSe2]
_chemical_formula_sum '[Mg4 Zn4 Se8]'
_cell_volume [405.2040]
_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  4  0.0870  0.8765  0.0011  1.0
  Zn  Zn1  4  0.0806  0.3749  0.9997  1.0
  Se  Se2  4  0.0748  0.3810  0.6319  1.0
  Se  Se3  4  0.0903  0.8681  0.6171  1.0
]