The crystal structure described by Al3Hf is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Hf(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Al(3) atoms to form HfAl12 cuboctahedra that share corners with four equivalent Al(1)Hf4Al8 cuboctahedra, corners with eight equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Al(3)Hf4Al8 cuboctahedra, faces with five equivalent Hf(1)Al12 cuboctahedra, and faces with five equivalent Al(1)Hf4Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Hf(1), four equivalent Al(2), and four equivalent Al(3) atoms to form distorted AlHf4Al8 cuboctahedra that share corners with four equivalent Hf(1)Al12 cuboctahedra, corners with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with four equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Al(3)Hf4Al8 cuboctahedra, faces with five equivalent Hf(1)Al12 cuboctahedra, and faces with five equivalent Al(1)Hf4Al8 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlHf4Al8 cuboctahedra that share corners with four equivalent Al(2)Hf4Al8 cuboctahedra, corners with eight equivalent Al(3)Hf4Al8 cuboctahedra, edges with eight equivalent Hf(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with two equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Hf(1)Al12 cuboctahedra, faces with four equivalent Al(1)Hf4Al8 cuboctahedra, and faces with eight equivalent Al(2)Hf4Al8 cuboctahedra. In the third Al site, Al(3) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(3) atoms to form AlHf4Al8 cuboctahedra that share corners with four equivalent Al(3)Hf4Al8 cuboctahedra, corners with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Hf(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, faces with two equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Hf(1)Al12 cuboctahedra, faces with four equivalent Al(1)Hf4Al8 cuboctahedra, and faces with eight equivalent Al(3)Hf4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_HfAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.970
_cell_length_b   3.970
_cell_length_c   8.992
_cell_angle_alpha   102.739
_cell_angle_beta   102.739
_cell_angle_gamma   90.021
_symmetry_Int_Tables_number   1
_cell_volume   134.660
_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  0.119  0.119  0.239  1.0
  Hf  Hf1  1  0.881  0.881  0.761  1.0
  Al  Al2  1  0.375  0.375  0.750  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.625  0.625  0.250  1.0
  Al  Al5  1  0.250  0.750  0.500  1.0
  Al  Al6  1  0.750  0.250  0.500  1.0
  Al  Al7  1  0.500  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Al3Hf is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Hf(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Al(3) atoms to form HfAl12 cuboctahedra that share corners with four equivalent Al(1)Hf4Al8 cuboctahedra, corners with eight equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Al(3)Hf4Al8 cuboctahedra, faces with five equivalent Hf(1)Al12 cuboctahedra, and faces with five equivalent Al(1)Hf4Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Hf(1), four equivalent Al(2), and four equivalent Al(3) atoms to form distorted AlHf4Al8 cuboctahedra that share corners with four equivalent Hf(1)Al12 cuboctahedra, corners with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with four equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Al(3)Hf4Al8 cuboctahedra, faces with five equivalent Hf(1)Al12 cuboctahedra, and faces with five equivalent Al(1)Hf4Al8 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlHf4Al8 cuboctahedra that share corners with four equivalent Al(2)Hf4Al8 cuboctahedra, corners with eight equivalent Al(3)Hf4Al8 cuboctahedra, edges with eight equivalent Hf(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(3)Hf4Al8 cuboctahedra, faces with two equivalent Al(3)Hf4Al8 cuboctahedra, faces with four equivalent Hf(1)Al12 cuboctahedra, faces with four equivalent Al(1)Hf4Al8 cuboctahedra, and faces with eight equivalent Al(2)Hf4Al8 cuboctahedra. In the third Al site, Al(3) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(3) atoms to form AlHf4Al8 cuboctahedra that share corners with four equivalent Al(3)Hf4Al8 cuboctahedra, corners with eight equivalent Al(2)Hf4Al8 cuboctahedra, edges with eight equivalent Hf(1)Al12 cuboctahedra, edges with eight equivalent Al(1)Hf4Al8 cuboctahedra, edges with eight equivalent Al(2)Hf4Al8 cuboctahedra, faces with two equivalent Al(2)Hf4Al8 cuboctahedra, faces with four equivalent Hf(1)Al12 cuboctahedra, faces with four equivalent Al(1)Hf4Al8 cuboctahedra, and faces with eight equivalent Al(3)Hf4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_HfAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.970
_cell_length_b   3.970
_cell_length_c   8.992
_cell_angle_alpha   102.739
_cell_angle_beta   102.739
_cell_angle_gamma   90.021
_symmetry_Int_Tables_number   1
_cell_volume   134.660
_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  0.119  0.119  0.239  1.0
  Hf  Hf1  1  0.881  0.881  0.761  1.0
  Al  Al2  1  0.375  0.375  0.750  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.625  0.625  0.250  1.0
  Al  Al5  1  0.250  0.750  0.500  1.0
  Al  Al6  1  0.750  0.250  0.500  1.0
  Al  Al7  1  0.500  0.000  0.000  1.0
[/CIF]
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