data_Mg(ZnSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.21
_cell_length_b   5.21
_cell_length_c   8.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   89.25
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg(ZnSe)2
_chemical_formula_sum   'Mg2 Zn4 Se4'
_cell_volume   229.22
_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
  Mg  Mg0  1  0.71  0.64  0.11  1.0
  Mg  Mg1  1  0.71  0.36  0.34  1.0
  Zn  Zn6  1  0.71  0.81  0.13  1.0
  Zn  Zn7  1  0.71  0.19  0.9  1.0
  Zn  Zn8  1  0.71  0.81  0.56  1.0
  Zn  Zn9  1  0.71  0.19  0.33  1.0
  Se  Se2  1  0.66  0.0  0.0  1.0
  Se  Se3  1  0.75  0.0  0.23  1.0
  Se  Se4  1  0.75  0.0  0.0  1.0
  Se  Se5  1  0.66  0.0  0.23  1.0

data_Mg(ZnSe)2
_symmetry_space_group_name_H-M   Pm
_cell_length_a   5.21
_cell_length_b   5.21
_cell_length_c   8.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   Mg(ZnSe)2
_chemical_formula_sum   'Mg2 Zn4 Se4'
_cell_volume   229.24
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '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  1  0.36  0.0  0.34  1.0
  Mg  Mg1  1  0.64  0.0  0.11  1.0
  Zn  Zn2  1  0.19  0.0  0.33  1.0
  Zn  Zn3  1  0.19  0.0  0.9  1.0
  Zn  Zn4  1  0.81  0.0  0.13  1.0
  Zn  Zn5  1  0.81  0.0  0.56  1.0
  Se  Se6  2  0.0  0.05  0.23  1.0
  Se  Se7  2  0.0  0.05  -0.0  1.0

Mg Mg Zn Zn Zn Zn Se Se Se Se