data_MgSeCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.53
_cell_length_b   7.33
_cell_length_c   3.24
_cell_angle_alpha   80.88
_cell_angle_beta   74.0
_cell_angle_gamma   25.12
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSeCl
_chemical_formula_sum   'Mg1 Se1 Cl1'
_cell_volume   71.19
_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  0.94  0.59  0.3  1.0
  Se  Se2  1  0.94  0.59  0.14  1.0
  Cl  Cl0  1  0.94  0.59  0.71  1.0

data_MgSeCl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.88
_cell_length_b   14.15
_cell_length_c   3.24
_cell_angle_alpha   90.0
_cell_angle_beta   126.81
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   MgSeCl
_chemical_formula_sum   'Mg2 Se2 Cl2'
_cell_volume   142.38
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.44  0.5  0.24  1.0
  Se  Se1  2  0.44  0.5  0.08  1.0
  Cl  Cl2  2  0.44  0.5  0.65  1.0

Mg Se Cl