The structure described by Al6C3N2 crystallizes in the monoclinic Pm space group. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 5-coordinate geometry to one C(2), two equivalent C(3), and two equivalent N(2) atoms. In the second Al site, Al(2) is bonded in a distorted bent 150 degrees geometry to one C(1) and one C(2) atom. In the third Al site, Al(3) is bonded in a bent 120 degrees geometry to two equivalent C(2) atoms. In the fourth Al site, Al(4) is bonded in a distorted see-saw-like geometry to two equivalent C(1) and two equivalent N(1) atoms. In the fifth Al site, Al(5) is bonded to two equivalent C(3), one N(1), and two equivalent N(2) atoms to form AlC2N3 trigonal bipyramids that share corners with two equivalent C(2)Al4N trigonal bipyramids, corners with four equivalent Al(5)C2N3 trigonal bipyramids, and edges with two equivalent Al(6)C3N2 trigonal bipyramids. In the sixth Al site, Al(6) is bonded to one C(3), two equivalent C(1), and two equivalent N(1) atoms to form AlC3N2 trigonal bipyramids that share corners with four equivalent Al(6)C3N2 trigonal bipyramids and edges with two equivalent Al(5)C2N3 trigonal bipyramids. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Al(2), two equivalent Al(4), and two equivalent Al(6) atoms to form CAl5 trigonal bipyramids that share  a cornercorner with one C(2)Al4N trigonal bipyramid, corners with two equivalent C(3)Al5 trigonal bipyramids, corners with four equivalent C(1)Al5 trigonal bipyramids, and edges with four equivalent N(1)Al5 trigonal bipyramids. In the second C site, C(2) is bonded to one Al(1), one Al(2), two equivalent Al(3), and one N(2) atom to form distorted CAl4N trigonal bipyramids that share  a cornercorner with one C(1)Al5 trigonal bipyramid, corners with two equivalent Al(5)C2N3 trigonal bipyramids, corners with two equivalent C(2)Al4N trigonal bipyramids, and corners with two equivalent C(3)Al5 trigonal bipyramids. In the third C site, C(3) is bonded to one Al(6), two equivalent Al(1), and two equivalent Al(5) atoms to form CAl5 trigonal bipyramids that share corners with two equivalent C(2)Al4N trigonal bipyramids, corners with two equivalent C(1)Al5 trigonal bipyramids, corners with four equivalent C(3)Al5 trigonal bipyramids, and edges with two equivalent N(1)Al5 trigonal bipyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Al(5), two equivalent Al(4), and two equivalent Al(6) atoms to form NAl5 trigonal bipyramids that share corners with four equivalent N(1)Al5 trigonal bipyramids, edges with two equivalent C(3)Al5 trigonal bipyramids, and edges with four equivalent C(1)Al5 trigonal bipyramids. In the second N site, N(2) is bonded in a 5-coordinate geometry to two equivalent Al(1), two equivalent Al(5), and one C(2) atom. is represented by the CIF card [CIF]
data_Al6C3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.479
_cell_length_b   4.165
_cell_length_c   9.232
_cell_angle_alpha   78.217
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   130.957
_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  0.500  0.277  0.750  1.0
  Al  Al1  1  0.500  0.072  0.392  1.0
  Al  Al2  1  0.000  0.512  0.513  1.0
  Al  Al3  1  0.500  0.628  0.143  1.0
  Al  Al4  1  0.000  0.758  0.835  1.0
  Al  Al5  1  0.000  0.162  0.064  1.0
  C  C6  1  0.500  0.105  0.181  1.0
  C  C7  1  0.500  0.703  0.579  1.0
  C  C8  1  0.000  0.262  0.838  1.0
  N  N9  1  0.000  0.665  0.053  1.0
  N  N10  1  0.500  0.828  0.717  1.0
[/CIF]
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The structure described by Al6C3N2 crystallizes in the monoclinic Pm space group. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 5-coordinate geometry to one C(2), two equivalent C(3), and two equivalent N(2) atoms. In the second Al site, Al(2) is bonded in a distorted bent 150 degrees geometry to one C(1) and one C(2) atom. In the third Al site, Al(3) is bonded in a bent 120 degrees geometry to two equivalent C(2) atoms. In the fourth Al site, Al(4) is bonded in a distorted see-saw-like geometry to two equivalent C(1) and two equivalent N(1) atoms. In the fifth Al site, Al(5) is bonded to two equivalent C(3), one N(1), and two equivalent N(2) atoms to form AlC2N3 trigonal bipyramids that share corners with two equivalent C(2)Al4N trigonal bipyramids, corners with four equivalent Al(5)C2N3 trigonal bipyramids, and edges with two equivalent Al(6)C3N2 trigonal bipyramids. In the sixth Al site, Al(6) is bonded to one C(3), two equivalent C(1), and two equivalent N(1) atoms to form AlC3N2 trigonal bipyramids that share corners with four equivalent Al(6)C3N2 trigonal bipyramids and edges with two equivalent Al(5)C2N3 trigonal bipyramids. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Al(2), two equivalent Al(4), and two equivalent Al(6) atoms to form CAl5 trigonal bipyramids that share  a cornercorner with one C(2)Al4N trigonal bipyramid, corners with two equivalent C(3)Al5 trigonal bipyramids, corners with four equivalent C(1)Al5 trigonal bipyramids, and edges with four equivalent N(1)Al5 trigonal bipyramids. In the second C site, C(2) is bonded to one Al(1), one Al(2), two equivalent Al(3), and one N(2) atom to form distorted CAl4N trigonal bipyramids that share  a cornercorner with one C(1)Al5 trigonal bipyramid, corners with two equivalent Al(5)C2N3 trigonal bipyramids, corners with two equivalent C(2)Al4N trigonal bipyramids, and corners with two equivalent C(3)Al5 trigonal bipyramids. In the third C site, C(3) is bonded to one Al(6), two equivalent Al(1), and two equivalent Al(5) atoms to form CAl5 trigonal bipyramids that share corners with two equivalent C(2)Al4N trigonal bipyramids, corners with two equivalent C(1)Al5 trigonal bipyramids, corners with four equivalent C(3)Al5 trigonal bipyramids, and edges with two equivalent N(1)Al5 trigonal bipyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Al(5), two equivalent Al(4), and two equivalent Al(6) atoms to form NAl5 trigonal bipyramids that share corners with four equivalent N(1)Al5 trigonal bipyramids, edges with two equivalent C(3)Al5 trigonal bipyramids, and edges with four equivalent C(1)Al5 trigonal bipyramids. In the second N site, N(2) is bonded in a 5-coordinate geometry to two equivalent Al(1), two equivalent Al(5), and one C(2) atom. is represented by the CIF card [CIF]
data_Al6C3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.479
_cell_length_b   4.165
_cell_length_c   9.232
_cell_angle_alpha   78.217
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   130.957
_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  0.500  0.277  0.750  1.0
  Al  Al1  1  0.500  0.072  0.392  1.0
  Al  Al2  1  0.000  0.512  0.513  1.0
  Al  Al3  1  0.500  0.628  0.143  1.0
  Al  Al4  1  0.000  0.758  0.835  1.0
  Al  Al5  1  0.000  0.162  0.064  1.0
  C  C6  1  0.500  0.105  0.181  1.0
  C  C7  1  0.500  0.703  0.579  1.0
  C  C8  1  0.000  0.262  0.838  1.0
  N  N9  1  0.000  0.665  0.053  1.0
  N  N10  1  0.500  0.828  0.717  1.0
[/CIF]
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