data_Mg2Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.26
_cell_length_b   3.26
_cell_length_c   15.91
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2Sn
_chemical_formula_sum   'Mg4 Sn2'
_cell_volume   146.6
_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  0.0  0.88  0.59  1.0
  Mg  Mg1  1  0.63  0.94  1.0  1.0
  Mg  Mg2  1  0.0  0.88  0.92  1.0
  Mg  Mg3  1  0.63  0.94  0.32  1.0
  Sn  Sn4  1  0.0  0.88  0.4  1.0
  Sn  Sn5  1  0.63  0.94  0.52  1.0

data_Mg2Sn
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.26
_cell_length_b   3.26
_cell_length_c   15.91
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Mg2Sn
_chemical_formula_sum   'Mg4 Sn2'
_cell_volume   146.6
_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  2  0.32  0.53  0.86  1.0
  Mg  Mg1  2  0.32  0.53  0.54  1.0
  Sn  Sn2  2  0.32  0.53  0.06  1.0

Mg Mg Mg Mg Sn Sn