data_PbC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.45
_cell_length_b   4.45
_cell_length_c   4.45
_cell_angle_alpha   126.06
_cell_angle_beta   124.47
_cell_angle_gamma   81.11
_symmetry_Int_Tables_number   1
_chemical_formula_structural   PbC2
_chemical_formula_sum   'Pb1 C2'
_cell_volume   56.57
_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
  Pb  Pb2  1  0.0  0.0  0.0  1.0
  C  C0  1  0.0  0.0  0.75  1.0
  C  C1  1  0.0  0.0  0.02  1.0

data_PbC2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.04
_cell_length_b   4.15
_cell_length_c   4.45
_cell_angle_alpha   117.77
_cell_angle_beta   116.97
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   PbC2
_chemical_formula_sum   'Pb1 C2'
_cell_volume   56.57
_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
  Pb  Pb0  1  0.0  0.0  0.0  1.0
  C  C1  1  0.0  0.02  0.02  1.0
  C  C2  1  0.0  0.75  0.75  1.0

Pb C C