data_Si3C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.02
_cell_length_b   4.02
_cell_length_c   3.09
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   101.05
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si3C
_chemical_formula_sum   'Si3 C1'
_cell_volume   49.0
_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  0.28  0.55  0.55  1.0
  Si  Si2  1  0.28  0.45  0.55  1.0
  Si  Si3  1  0.55  0.0  0.0  1.0
  C  C0  1  0.0  0.0  0.0  1.0

data_Si3C
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.09
_cell_length_b   4.02
_cell_length_c   4.02
_cell_angle_alpha   101.05
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Si3C
_chemical_formula_sum   'Si3 C1'
_cell_volume   49.0
_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  Si0  1  0.0  0.55  0.0  1.0
  Si  Si1  1  0.55  0.28  0.45  1.0
  Si  Si2  1  0.55  0.28  0.55  1.0
  C  C3  1  0.0  0.0  0.0  1.0

Si Si Si C
Si Si Si C 0 1 o o o 2 3 + o o 