data_BC3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.77
_cell_length_b   3.77
_cell_length_c   3.77
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BC3
_chemical_formula_sum   'B2 C6'
_cell_volume   53.69
_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
  B  B0  1  0.89  0.89  0.89  1.0
  B  B1  1  0.0  0.0  0.0  1.0
  C  C2  1  0.94  0.0  0.89  1.0
  C  C3  1  0.83  0.0  0.89  1.0
  C  C4  1  0.89  0.94  0.0  1.0
  C  C5  1  0.89  0.83  0.0  1.0
  C  C6  1  0.0  0.89  0.83  1.0
  C  C7  1  0.0  0.89  0.94  1.0

data_BC3
_symmetry_space_group_name_H-M   R3
_cell_length_a   5.34
_cell_length_b   5.34
_cell_length_c   6.53
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   BC3
_chemical_formula_sum   'B6 C18'
_cell_volume   161.07
_cell_formula_units_Z   6
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  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+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
  B  B0  3  0.0  0.0  0.0  1.0
  B  B1  3  0.0  0.0  0.89  1.0
  C  C2  9  0.0  0.06  0.94  1.0
  C  C3  9  0.09  0.08  0.91  1.0

B B C C C C C C
B B C C C C C C 0 3 o + o 0 5 o o + 0 6 + o o 0 7 + o o 0 2 o + o 0 4 o o + 1 4 - - o 1 2 - o - 1 7 o - - 2 4 o - + 2 3 o o o 2 6 + - o 2 7 + - o 3 4 o - + 4 7 + o - 4 5 o o o 5 7 + o - 6 7 o o o 
BC3 is alpha Po structured and crystallizes in the trigonal R3 space group. The structure is zero-dimensional and consists of three BC3 clusters. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 3-coordinate geometry to three equivalent C(1) and three equivalent C(2) atoms. All B(1)-C(1) bond lengths are 0.48 Å. All B(1)-C(2) bond lengths are 0.48 Å. In the second B site, B(2) is bonded in a 3-coordinate geometry to three equivalent C(1) atoms. All B(2)-C(1) bond lengths are 0.48 Å. There are two inequivalent C sites. In the first C site, C(1) is bonded in a single-bond geometry to one B(1), one B(2), and two equivalent C(2) atoms. There is one shorter (0.43 Å) and one longer (0.53 Å) C(1)-C(2) bond length. In the second C site, C(2) is bonded in a 3-coordinate geometry to one B(1) and two equivalent C(1) atoms.