data_Ca2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.08
_cell_length_b   7.08
_cell_length_c   7.42
_cell_angle_alpha   116.61
_cell_angle_beta   116.61
_cell_angle_gamma   34.9
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca2Si
_chemical_formula_sum   'Ca4 Si2'
_cell_volume   187.94
_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
  Ca  Ca0  1  0.29  0.0  0.98  1.0
  Ca  Ca1  1  0.14  0.0  0.68  1.0
  Ca  Ca2  1  0.89  0.0  0.87  1.0
  Ca  Ca3  1  0.74  0.0  0.56  1.0
  Si  Si4  1  0.88  0.0  0.11  1.0
  Si  Si5  1  0.15  0.0  0.44  1.0

data_Ca2Si
_symmetry_space_group_name_H-M   P-1
_cell_length_a   4.25
_cell_length_b   7.08
_cell_length_c   7.42
_cell_angle_alpha   116.61
_cell_angle_beta   90.0
_cell_angle_gamma   107.45
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Ca2Si
_chemical_formula_sum   'Ca4 Si2'
_cell_volume   187.94
_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
  Ca  Ca0  2  0.0  0.22  0.79  1.0
  Ca  Ca1  2  0.0  0.38  0.1  1.0
  Si  Si2  2  0.0  0.36  0.34  1.0

Ca Ca Ca Ca Si Si
Ca Ca Ca Ca Si Si 0 1 o o o 1 5 o o o 2 3 o o o 2 4 o o + 