data_Si2P
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.3
_cell_length_b   9.3
_cell_length_c   9.3
_cell_angle_alpha   160.28
_cell_angle_beta   160.12
_cell_angle_gamma   28.14
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si2P
_chemical_formula_sum   'Si4 P2'
_cell_volume   92.17
_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
  Si  Si2  1  0.59  0.2  0.05  1.0
  Si  Si3  1  0.0  0.41  0.97  1.0
  Si  Si4  1  0.59  0.2  0.51  1.0
  Si  Si5  1  0.0  0.41  0.51  1.0
  P  P0  1  0.0  0.8  0.71  1.0
  P  P1  1  0.59  0.8  0.31  1.0

data_Si2P
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.18
_cell_length_b   3.21
_cell_length_c   9.3
_cell_angle_alpha   99.94
_cell_angle_beta   99.86
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Si2P
_chemical_formula_sum   'Si4 P2'
_cell_volume   92.17
_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
  Si  Si0  2  0.4  0.35  0.15  1.0
  Si  Si1  2  0.4  0.9  0.7  1.0
  P  P2  2  0.0  0.3  0.5  1.0

Si Si Si Si P P
Si Si Si Si P P 0 3 + o o 1 2 - o o 2 5 o - o 3 4 o o o 4 5 - o o 