The crystal structure described by Hf2Al3C5 crystallizes in the hexagonal P6_3/mmc space group. Hf(1) is bonded to three equivalent C(2) and three equivalent C(3) atoms to form HfC6 octahedra that share corners with three equivalent Hf(1)C6 octahedra, corners with three equivalent Al(1)C6 octahedra, edges with three equivalent Al(1)C6 octahedra, and edges with nine equivalent Hf(1)C6 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form AlC6 octahedra that share corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(1)C6 octahedra, and edges with six equivalent Al(1)C6 octahedra. The corner-sharing octahedral tilt angles are 8°. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to six equivalent C(1) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to three equivalent Al(1), three equivalent Al(2), and one C(1) atom. In the second C site, C(2) is bonded to three equivalent Hf(1) and three equivalent Al(1) atoms to form CHf3Al3 octahedra that share corners with three equivalent C(3)Hf6 octahedra, edges with three equivalent C(3)Hf6 octahedra, and edges with six equivalent C(2)Hf3Al3 octahedra. The corner-sharing octahedra are not tilted. In the third C site, C(3) is bonded to six equivalent Hf(1) atoms to form CHf6 octahedra that share corners with six equivalent C(2)Hf3Al3 octahedra, edges with six equivalent C(2)Hf3Al3 octahedra, and edges with six equivalent C(3)Hf6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Hf2Al3C5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.225
_cell_length_b   3.225
_cell_length_c   24.321
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   219.034
_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
  Hf  Hf0  1  0.667  0.333  0.944  1.0
  Hf  Hf1  1  0.333  0.667  0.444  1.0
  Hf  Hf2  1  0.667  0.333  0.556  1.0
  Hf  Hf3  1  0.333  0.667  0.056  1.0
  Al  Al4  1  0.000  0.000  0.846  1.0
  Al  Al5  1  0.000  0.000  0.346  1.0
  Al  Al6  1  0.000  0.000  0.154  1.0
  Al  Al7  1  0.000  0.000  0.654  1.0
  Al  Al8  1  0.333  0.667  0.750  1.0
  Al  Al9  1  0.667  0.333  0.250  1.0
  C  C10  1  0.667  0.333  0.784  1.0
  C  C11  1  0.333  0.667  0.284  1.0
  C  C12  1  0.333  0.667  0.887  1.0
  C  C13  1  0.667  0.333  0.387  1.0
  C  C14  1  0.667  0.333  0.113  1.0
  C  C15  1  0.333  0.667  0.613  1.0
  C  C16  1  0.333  0.667  0.216  1.0
  C  C17  1  0.667  0.333  0.716  1.0
  C  C18  1  0.000  0.000  0.000  1.0
  C  C19  1  0.000  0.000  0.500  1.0
[/CIF]
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The crystal structure described by Hf2Al3C5 crystallizes in the hexagonal P6_3/mmc space group. Hf(1) is bonded to three equivalent C(2) and three equivalent C(3) atoms to form HfC6 octahedra that share corners with three equivalent Hf(1)C6 octahedra, corners with three equivalent Al(1)C6 octahedra, edges with three equivalent Al(1)C6 octahedra, and edges with nine equivalent Hf(1)C6 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent C(1) and three equivalent C(2) atoms to form AlC6 octahedra that share corners with three equivalent Hf(1)C6 octahedra, edges with three equivalent Hf(1)C6 octahedra, and edges with six equivalent Al(1)C6 octahedra. The corner-sharing octahedral tilt angles are 8°. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to six equivalent C(1) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to three equivalent Al(1), three equivalent Al(2), and one C(1) atom. In the second C site, C(2) is bonded to three equivalent Hf(1) and three equivalent Al(1) atoms to form CHf3Al3 octahedra that share corners with three equivalent C(3)Hf6 octahedra, edges with three equivalent C(3)Hf6 octahedra, and edges with six equivalent C(2)Hf3Al3 octahedra. The corner-sharing octahedra are not tilted. In the third C site, C(3) is bonded to six equivalent Hf(1) atoms to form CHf6 octahedra that share corners with six equivalent C(2)Hf3Al3 octahedra, edges with six equivalent C(2)Hf3Al3 octahedra, and edges with six equivalent C(3)Hf6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Hf2Al3C5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.225
_cell_length_b   3.225
_cell_length_c   24.321
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   219.034
_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
  Hf  Hf0  1  0.667  0.333  0.944  1.0
  Hf  Hf1  1  0.333  0.667  0.444  1.0
  Hf  Hf2  1  0.667  0.333  0.556  1.0
  Hf  Hf3  1  0.333  0.667  0.056  1.0
  Al  Al4  1  0.000  0.000  0.846  1.0
  Al  Al5  1  0.000  0.000  0.346  1.0
  Al  Al6  1  0.000  0.000  0.154  1.0
  Al  Al7  1  0.000  0.000  0.654  1.0
  Al  Al8  1  0.333  0.667  0.750  1.0
  Al  Al9  1  0.667  0.333  0.250  1.0
  C  C10  1  0.667  0.333  0.784  1.0
  C  C11  1  0.333  0.667  0.284  1.0
  C  C12  1  0.333  0.667  0.887  1.0
  C  C13  1  0.667  0.333  0.387  1.0
  C  C14  1  0.667  0.333  0.113  1.0
  C  C15  1  0.333  0.667  0.613  1.0
  C  C16  1  0.333  0.667  0.216  1.0
  C  C17  1  0.667  0.333  0.716  1.0
  C  C18  1  0.000  0.000  0.000  1.0
  C  C19  1  0.000  0.000  0.500  1.0
[/CIF]
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