data_PtC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.55
_cell_length_b   3.55
_cell_length_c   3.55
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   PtC2
_chemical_formula_sum   'Pt1 C2'
_cell_volume   31.76
_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
  Pt  Pt2  1  0.0  0.0  0.0  1.0
  C  C0  1  0.26  0.26  0.26  1.0
  C  C1  1  0.77  0.77  0.77  1.0

data_PtC2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.55
_cell_length_b   3.55
_cell_length_c   8.71
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   PtC2
_chemical_formula_sum   'Pt3 C6'
_cell_volume   95.29
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Pt  Pt0  3  0.0  0.0  0.0  1.0
  C  C1  3  0.0  0.0  0.23  1.0
  C  C2  3  0.0  0.0  0.74  1.0

Pt C C
Pt C C 0 2 - - - 0 2 - - o 0 2 o - - 0 2 - o - 0 1 - o o 0 1 o - o 0 1 o o - 0 1 o o o 1 2 - - o 1 2 - o - 1 2 - o o 1 2 o - - 1 2 o - o 1 2 o o - 
PtC2 is Fluorite structured and crystallizes in the trigonal R3m space group. Pt(1) is bonded in a body-centered cubic geometry to four equivalent C(1) and four equivalent C(2) atoms. There are three shorter (2.16 Å) and one longer (2.24 Å) Pt(1)-C(1) bond length. There is one shorter (2.00 Å) and three longer (2.24 Å) Pt(1)-C(2) bond lengths. There are two inequivalent C sites. In the first C site, C(1) is bonded to four equivalent Pt(1) atoms to form a mixture of edge and corner-sharing CPt4 tetrahedra. In the second C site, C(2) is bonded to four equivalent Pt(1) atoms to form a mixture of edge and corner-sharing CPt4 tetrahedra.