The compound described by YAl3C3 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form YC6 octahedra that share corners with three equivalent Al(1)C4 tetrahedra, corners with three equivalent Al(2)C4 tetrahedra, edges with six equivalent Y(1)C6 octahedra, edges with three equivalent Al(1)C4 tetrahedra, and edges with three equivalent Al(2)C4 tetrahedra. In the second Y site, Y(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form YC6 octahedra that share corners with three equivalent Al(1)C4 tetrahedra, corners with three equivalent Al(2)C4 tetrahedra, edges with six equivalent Y(1)C6 octahedra, edges with three equivalent Al(1)C4 tetrahedra, and edges with three equivalent Al(2)C4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(3) and three equivalent C(2) atoms to form AlC4 tetrahedra that share corners with three equivalent Y(1)C6 octahedra,  a cornercorner with one Al(2)C4 tetrahedra, corners with six equivalent Al(1)C4 tetrahedra, and edges with three equivalent Y(1)C6 octahedra. The corner-sharing octahedral tilt angles are 18°. In the second Al site, Al(2) is bonded to one C(3) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Y(1)C6 octahedra,  a cornercorner with one Al(1)C4 tetrahedra, corners with six equivalent Al(2)C4 tetrahedra, and edges with three equivalent Y(1)C6 octahedra. The corner-sharing octahedral tilt angles are 18°. In the third Al site, Al(3) is bonded in a trigonal planar geometry to three equivalent C(3) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Y(1) and three equivalent Al(2) atoms. In the second C site, C(2) is bonded to three equivalent Y(1) and three equivalent Al(1) atoms to form distorted CY3Al3 octahedra that share corners with three equivalent C(3)Al5 trigonal bipyramids and edges with six equivalent C(2)Y3Al3 octahedra. In the third C site, C(3) is bonded to one Al(1), one Al(2), and three equivalent Al(3) atoms to form CAl5 trigonal bipyramids that share corners with three equivalent C(2)Y3Al3 octahedra and corners with six equivalent C(3)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 69°. is represented by the CIF card [CIF]
data_Y(AlC)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.439
_cell_length_b   3.439
_cell_length_c   17.344
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   177.651
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.000  0.000  0.500  1.0
  Al  Al2  1  0.333  0.667  0.364  1.0
  Al  Al3  1  0.667  0.333  0.864  1.0
  Al  Al4  1  0.333  0.667  0.136  1.0
  Al  Al5  1  0.667  0.333  0.636  1.0
  Al  Al6  1  0.333  0.667  0.745  1.0
  Al  Al7  1  0.667  0.333  0.245  1.0
  C  C8  1  0.333  0.667  0.593  1.0
  C  C9  1  0.667  0.333  0.093  1.0
  C  C10  1  0.333  0.667  0.907  1.0
  C  C11  1  0.667  0.333  0.407  1.0
  C  C12  1  0.333  0.667  0.250  1.0
  C  C13  1  0.667  0.333  0.750  1.0
[/CIF]
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The compound described by YAl3C3 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form YC6 octahedra that share corners with three equivalent Al(1)C4 tetrahedra, corners with three equivalent Al(2)C4 tetrahedra, edges with six equivalent Y(1)C6 octahedra, edges with three equivalent Al(1)C4 tetrahedra, and edges with three equivalent Al(2)C4 tetrahedra. In the second Y site, Y(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form YC6 octahedra that share corners with three equivalent Al(1)C4 tetrahedra, corners with three equivalent Al(2)C4 tetrahedra, edges with six equivalent Y(1)C6 octahedra, edges with three equivalent Al(1)C4 tetrahedra, and edges with three equivalent Al(2)C4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one C(3) and three equivalent C(2) atoms to form AlC4 tetrahedra that share corners with three equivalent Y(1)C6 octahedra,  a cornercorner with one Al(2)C4 tetrahedra, corners with six equivalent Al(1)C4 tetrahedra, and edges with three equivalent Y(1)C6 octahedra. The corner-sharing octahedral tilt angles are 18°. In the second Al site, Al(2) is bonded to one C(3) and three equivalent C(1) atoms to form AlC4 tetrahedra that share corners with three equivalent Y(1)C6 octahedra,  a cornercorner with one Al(1)C4 tetrahedra, corners with six equivalent Al(2)C4 tetrahedra, and edges with three equivalent Y(1)C6 octahedra. The corner-sharing octahedral tilt angles are 18°. In the third Al site, Al(3) is bonded in a trigonal planar geometry to three equivalent C(3) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 6-coordinate geometry to three equivalent Y(1) and three equivalent Al(2) atoms. In the second C site, C(2) is bonded to three equivalent Y(1) and three equivalent Al(1) atoms to form distorted CY3Al3 octahedra that share corners with three equivalent C(3)Al5 trigonal bipyramids and edges with six equivalent C(2)Y3Al3 octahedra. In the third C site, C(3) is bonded to one Al(1), one Al(2), and three equivalent Al(3) atoms to form CAl5 trigonal bipyramids that share corners with three equivalent C(2)Y3Al3 octahedra and corners with six equivalent C(3)Al5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 69°. is represented by the CIF card [CIF]
data_Y(AlC)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.439
_cell_length_b   3.439
_cell_length_c   17.344
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   177.651
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.000  0.000  0.500  1.0
  Al  Al2  1  0.333  0.667  0.364  1.0
  Al  Al3  1  0.667  0.333  0.864  1.0
  Al  Al4  1  0.333  0.667  0.136  1.0
  Al  Al5  1  0.667  0.333  0.636  1.0
  Al  Al6  1  0.333  0.667  0.745  1.0
  Al  Al7  1  0.667  0.333  0.245  1.0
  C  C8  1  0.333  0.667  0.593  1.0
  C  C9  1  0.667  0.333  0.093  1.0
  C  C10  1  0.333  0.667  0.907  1.0
  C  C11  1  0.667  0.333  0.407  1.0
  C  C12  1  0.333  0.667  0.250  1.0
  C  C13  1  0.667  0.333  0.750  1.0
[/CIF]
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