The structure described by Al8BC5 is Aluminum carbonitride-like structured and crystallizes in the trigonal R-3m space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(1) and three equivalent C(3) atoms to form a mixture of distorted edge and corner-sharing AlC4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent B(1) and one C(2) atom to form distorted AlB3C tetrahedra that share corners with nine equivalent Al(2)B3C tetrahedra,  a cornercorner with one Al(4)C4 trigonal pyramid, corners with three equivalent Al(3)C4 trigonal pyramids, and edges with three equivalent Al(2)B3C tetrahedra. In the third Al site, Al(3) is bonded to one C(1) and three equivalent C(2) atoms to form AlC4 trigonal pyramids that share  a cornercorner with one Al(1)C4 tetrahedra, corners with three equivalent Al(2)B3C tetrahedra, corners with six equivalent Al(3)C4 trigonal pyramids, and edges with three equivalent Al(4)C4 trigonal pyramids. In the fourth Al site, Al(4) is bonded to one C(2) and three equivalent C(1) atoms to form distorted AlC4 trigonal pyramids that share  a cornercorner with one Al(2)B3C tetrahedra, corners with three equivalent Al(1)C4 tetrahedra, corners with six equivalent Al(4)C4 trigonal pyramids, and edges with three equivalent Al(3)C4 trigonal pyramids. B(1) is bonded to six equivalent Al(2) atoms to form BAl6 octahedra that share corners with six equivalent C(2)Al5 trigonal bipyramids and edges with six equivalent B(1)Al6 octahedra. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Al(1), one Al(3), and three equivalent Al(4) atoms to form distorted CAl5 trigonal bipyramids that share corners with three equivalent C(3)Al6 octahedra, corners with six equivalent C(1)Al5 trigonal bipyramids, and edges with three equivalent C(2)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. In the second C site, C(2) is bonded to one Al(2), one Al(4), and three equivalent Al(3) atoms to form CAl5 trigonal bipyramids that share corners with three equivalent B(1)Al6 octahedra, corners with six equivalent C(2)Al5 trigonal bipyramids, and edges with three equivalent C(1)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. In the third C site, C(3) is bonded to six equivalent Al(1) atoms to form CAl6 octahedra that share corners with six equivalent C(1)Al5 trigonal bipyramids and edges with six equivalent C(3)Al6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al8BC5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.944
_cell_length_b   16.944
_cell_length_c   16.944
_cell_angle_alpha   11.477
_cell_angle_beta   11.477
_cell_angle_gamma   11.477
_symmetry_Int_Tables_number   1
_cell_volume   167.348
_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
  Al  Al0  1  0.353  0.353  0.353  1.0
  Al  Al1  1  0.854  0.854  0.854  1.0
  Al  Al2  1  0.146  0.146  0.146  1.0
  Al  Al3  1  0.647  0.647  0.647  1.0
  Al  Al4  1  0.436  0.436  0.436  1.0
  Al  Al5  1  0.935  0.935  0.935  1.0
  Al  Al6  1  0.065  0.065  0.065  1.0
  Al  Al7  1  0.564  0.564  0.564  1.0
  B  B8  1  0.500  0.500  0.500  1.0
  C  C9  1  0.391  0.391  0.391  1.0
  C  C10  1  0.893  0.893  0.893  1.0
  C  C11  1  0.107  0.107  0.107  1.0
  C  C12  1  0.609  0.609  0.609  1.0
  C  C13  1  0.000  0.000  0.000  1.0
[/CIF]
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The structure described by Al8BC5 is Aluminum carbonitride-like structured and crystallizes in the trigonal R-3m space group. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(1) and three equivalent C(3) atoms to form a mixture of distorted edge and corner-sharing AlC4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent B(1) and one C(2) atom to form distorted AlB3C tetrahedra that share corners with nine equivalent Al(2)B3C tetrahedra,  a cornercorner with one Al(4)C4 trigonal pyramid, corners with three equivalent Al(3)C4 trigonal pyramids, and edges with three equivalent Al(2)B3C tetrahedra. In the third Al site, Al(3) is bonded to one C(1) and three equivalent C(2) atoms to form AlC4 trigonal pyramids that share  a cornercorner with one Al(1)C4 tetrahedra, corners with three equivalent Al(2)B3C tetrahedra, corners with six equivalent Al(3)C4 trigonal pyramids, and edges with three equivalent Al(4)C4 trigonal pyramids. In the fourth Al site, Al(4) is bonded to one C(2) and three equivalent C(1) atoms to form distorted AlC4 trigonal pyramids that share  a cornercorner with one Al(2)B3C tetrahedra, corners with three equivalent Al(1)C4 tetrahedra, corners with six equivalent Al(4)C4 trigonal pyramids, and edges with three equivalent Al(3)C4 trigonal pyramids. B(1) is bonded to six equivalent Al(2) atoms to form BAl6 octahedra that share corners with six equivalent C(2)Al5 trigonal bipyramids and edges with six equivalent B(1)Al6 octahedra. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Al(1), one Al(3), and three equivalent Al(4) atoms to form distorted CAl5 trigonal bipyramids that share corners with three equivalent C(3)Al6 octahedra, corners with six equivalent C(1)Al5 trigonal bipyramids, and edges with three equivalent C(2)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. In the second C site, C(2) is bonded to one Al(2), one Al(4), and three equivalent Al(3) atoms to form CAl5 trigonal bipyramids that share corners with three equivalent B(1)Al6 octahedra, corners with six equivalent C(2)Al5 trigonal bipyramids, and edges with three equivalent C(1)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. In the third C site, C(3) is bonded to six equivalent Al(1) atoms to form CAl6 octahedra that share corners with six equivalent C(1)Al5 trigonal bipyramids and edges with six equivalent C(3)Al6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al8BC5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.944
_cell_length_b   16.944
_cell_length_c   16.944
_cell_angle_alpha   11.477
_cell_angle_beta   11.477
_cell_angle_gamma   11.477
_symmetry_Int_Tables_number   1
_cell_volume   167.348
_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
  Al  Al0  1  0.353  0.353  0.353  1.0
  Al  Al1  1  0.854  0.854  0.854  1.0
  Al  Al2  1  0.146  0.146  0.146  1.0
  Al  Al3  1  0.647  0.647  0.647  1.0
  Al  Al4  1  0.436  0.436  0.436  1.0
  Al  Al5  1  0.935  0.935  0.935  1.0
  Al  Al6  1  0.065  0.065  0.065  1.0
  Al  Al7  1  0.564  0.564  0.564  1.0
  B  B8  1  0.500  0.500  0.500  1.0
  C  C9  1  0.391  0.391  0.391  1.0
  C  C10  1  0.893  0.893  0.893  1.0
  C  C11  1  0.107  0.107  0.107  1.0
  C  C12  1  0.609  0.609  0.609  1.0
  C  C13  1  0.000  0.000  0.000  1.0
[/CIF]
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