data_NaMg2Cl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.31
_cell_length_b   5.31
_cell_length_c   3.76
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaMg2Cl
_chemical_formula_sum   'Na1 Mg2 Cl1'
_cell_volume   105.92
_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
  Na  Na3  1  0.0  0.0  0.0  1.0
  Mg  Mg1  1  0.65  0.0  0.88  1.0
  Mg  Mg2  1  0.0  0.65  0.88  1.0
  Cl  Cl0  1  0.65  0.65  0.0  1.0

data_NaMg2Cl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.51
_cell_length_b   7.51
_cell_length_c   3.76
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaMg2Cl
_chemical_formula_sum   'Na2 Mg4 Cl2'
_cell_volume   211.84
_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
  Na  Na0  2  0.0  0.0  0.0  1.0
  Mg  Mg1  4  0.33  0.33  0.88  1.0
  Cl  Cl2  2  0.15  0.5  0.0  1.0

Na Mg Mg Cl
Na Mg Mg Cl 0 1 - o - 0 2 o - - 1 3 o - + 2 3 - o + 