data_Si3Pt
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.58
_cell_length_b   4.58
_cell_length_c   4.58
_cell_angle_alpha   126.98
_cell_angle_beta   126.98
_cell_angle_gamma   78.28
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si3Pt
_chemical_formula_sum   'Si3 Pt1'
_cell_volume   59.18
_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
  Si  Si1  1  0.0  0.04  0.77  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Si  Si3  1  0.04  0.0  0.77  1.0
  Pt  Pt0  1  0.0  0.0  0.55  1.0

data_Si3Pt
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.78
_cell_length_b   5.78
_cell_length_c   4.58
_cell_angle_alpha   90.0
_cell_angle_beta   129.14
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Si3Pt
_chemical_formula_sum   'Si6 Pt2'
_cell_volume   118.37
_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
  Si  Si0  4  0.25  0.02  0.27  1.0
  Si  Si1  2  0.0  0.0  0.0  1.0
  Pt  Pt2  2  0.45  0.0  0.45  1.0

Si Si Si Pt
Si Si Si Pt 0 2 o o o 0 1 o o + 0 3 o o o 1 2 o o - 2 3 o o o 