data_HgC3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.66
_cell_length_b   5.66
_cell_length_c   6.72
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   134.16
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgC3
_chemical_formula_sum   'Hg2 C6'
_cell_volume   154.59
_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
  Hg  Hg6  1  0.2  0.87  0.68  1.0
  Hg  Hg7  1  0.2  0.13  0.04  1.0
  C  C0  1  0.2  0.85  0.68  1.0
  C  C1  1  0.2  0.15  0.04  1.0
  C  C2  1  0.74  0.01  0.68  1.0
  C  C3  1  0.67  0.99  0.04  1.0
  C  C4  1  0.74  0.99  0.04  1.0
  C  C5  1  0.67  0.01  0.68  1.0

data_HgC3
_symmetry_space_group_name_H-M   P-1
_cell_length_a   4.41
_cell_length_b   5.66
_cell_length_c   6.72
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   112.92
_symmetry_Int_Tables_number   2
_chemical_formula_structural   HgC3
_chemical_formula_sum   'Hg2 C6'
_cell_volume   154.59
_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
  Hg  Hg0  2  0.13  0.13  0.32  1.0
  C  C1  2  0.01  0.48  0.68  1.0
  C  C2  2  0.01  0.54  0.68  1.0
  C  C3  2  0.15  0.15  0.32  1.0

Hg Hg C C C C C C