data_NaSn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.06
_cell_length_b   4.06
_cell_length_c   6.8
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaSn
_chemical_formula_sum   'Na2 Sn2'
_cell_volume   111.87
_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
  Na  Na0  1  0.03  0.0  0.88  1.0
  Na  Na1  1  0.0  0.03  0.92  1.0
  Sn  Sn2  1  0.03  0.0  0.7  1.0
  Sn  Sn3  1  0.0  0.03  0.1  1.0

data_NaSn
_symmetry_space_group_name_H-M   C2/m
_cell_length_a   5.74
_cell_length_b   5.74
_cell_length_c   6.8
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   12
_chemical_formula_structural   NaSn
_chemical_formula_sum   'Na4 Sn4'
_cell_volume   223.74
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-x, -y, -z'
  3  '-x, y, -z'
  4  'x, -y, z'
  5  'x+1/2, y+1/2, z'
  6  '-x+1/2, -y+1/2, -z'
  7  '-x+1/2, y+1/2, -z'
  8  '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  4  0.01  0.5  0.48  1.0
  Sn  Sn1  4  0.01  0.5  0.3  1.0

Na Na Sn Sn
Na Na Sn Sn 0 1 o o o 0 2 o o o 1 3 o o + 