data_Mg2SeCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.0
_cell_length_b   4.0
_cell_length_c   5.62
_cell_angle_alpha   90.0
_cell_angle_beta   90.27
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2SeCl
_chemical_formula_sum   'Mg2 Se1 Cl1'
_cell_volume   89.82
_cell_formula_units_Z   1
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  Mg1  1  0.97  0.0  0.72  1.0
  Mg  Mg2  1  0.97  0.0  0.47  1.0
  Se  Se3  1  0.99  0.0  0.53  1.0
  Cl  Cl0  1  0.04  0.0  0.71  1.0

data_Mg2SeCl
_symmetry_space_group_name_H-M   Pm
_cell_length_a   4.0
_cell_length_b   4.0
_cell_length_c   5.62
_cell_angle_alpha   90.0
_cell_angle_beta   90.27
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   Mg2SeCl
_chemical_formula_sum   'Mg2 Se1 Cl1'
_cell_volume   89.82
_cell_formula_units_Z   1
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  0.97  0.0  0.47  1.0
  Mg  Mg1  1  0.97  0.0  0.72  1.0
  Se  Se2  1  0.99  0.0  0.53  1.0
  Cl  Cl3  1  0.04  0.0  0.71  1.0

Mg Mg Se Cl
Mg Mg Se Cl 0 3 + o o 1 2 o o o 