data_Cu3Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.59
_cell_length_b   2.59
_cell_length_c   7.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu3Si
_chemical_formula_sum   'Cu3 Si1'
_cell_volume   49.27
_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
  Cu  Cu0  1  0.3  0.3  0.5  1.0
  Cu  Cu1  1  0.0  0.0  0.67  1.0
  Cu  Cu2  1  0.3  0.3  0.83  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Cu3Si
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.67
_cell_length_b   3.67
_cell_length_c   7.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Cu3Si
_chemical_formula_sum   'Cu6 Si2'
_cell_volume   98.54
_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  2  0.0  0.0  0.0  1.0
  Cu  Cu1  2  0.0  0.0  0.67  1.0
  Cu  Cu2  2  0.3  0.0  0.5  1.0
  Cu  Cu3  2  0.3  0.0  0.83  1.0

Cu Cu Cu Si
Cu Cu Cu Si 0 1 o o o 1 2 o o o 2 3 o o + 