The crystal structure described by HoAl3 crystallizes in the trigonal R-3m space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to six equivalent Al(1) and six equivalent Al(2) atoms to form HoAl12 cuboctahedra that share corners with six equivalent Ho(1)Al12 cuboctahedra, edges with six equivalent Al(1)Ho4Al8 cuboctahedra, faces with six equivalent Al(1)Ho4Al8 cuboctahedra, and faces with eight equivalent Ho(2)Al12 cuboctahedra. In the second Ho site, Ho(2) is bonded to three equivalent Al(1) and nine equivalent Al(2) atoms to form HoAl12 cuboctahedra that share corners with six equivalent Al(1)Ho4Al8 cuboctahedra, corners with nine equivalent Ho(2)Al12 cuboctahedra, edges with six equivalent Al(1)Ho4Al8 cuboctahedra, faces with three equivalent Ho(2)Al12 cuboctahedra, faces with three equivalent Al(1)Ho4Al8 cuboctahedra, and faces with four equivalent Ho(1)Al12 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(2) is bonded in a 10-coordinate geometry to one Ho(1), three equivalent Ho(2), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(1) is bonded to two equivalent Ho(1), two equivalent Ho(2), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlHo4Al8 cuboctahedra that share corners with four equivalent Ho(2)Al12 cuboctahedra, corners with six equivalent Al(1)Ho4Al8 cuboctahedra, edges with two equivalent Ho(1)Al12 cuboctahedra, edges with four equivalent Ho(2)Al12 cuboctahedra, edges with four equivalent Al(1)Ho4Al8 cuboctahedra, faces with two equivalent Ho(1)Al12 cuboctahedra, faces with two equivalent Ho(2)Al12 cuboctahedra, and faces with four equivalent Al(1)Ho4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_HoAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   7.845
_cell_angle_alpha   67.007
_cell_angle_beta   67.046
_cell_angle_gamma   60.002
_symmetry_Int_Tables_number   1
_cell_volume   227.817
_cell_formula_units_Z   3
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
  Ho  Ho0  1  0.000  0.000  0.000  1.0
  Ho  Ho1  1  0.218  0.218  0.345  1.0
  Ho  Ho2  1  0.782  0.782  0.655  1.0
  Al  Al3  1  0.500  0.500  0.000  1.0
  Al  Al4  1  0.500  0.000  0.000  1.0
  Al  Al5  1  0.000  0.500  0.000  1.0
  Al  Al6  1  0.297  0.297  0.668  1.0
  Al  Al7  1  0.297  0.738  0.668  1.0
  Al  Al8  1  0.738  0.297  0.668  1.0
  Al  Al9  1  0.703  0.703  0.332  1.0
  Al  Al10  1  0.703  0.262  0.332  1.0
  Al  Al11  1  0.262  0.703  0.332  1.0
[/CIF]
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The crystal structure described by HoAl3 crystallizes in the trigonal R-3m space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to six equivalent Al(1) and six equivalent Al(2) atoms to form HoAl12 cuboctahedra that share corners with six equivalent Ho(1)Al12 cuboctahedra, edges with six equivalent Al(1)Ho4Al8 cuboctahedra, faces with six equivalent Al(1)Ho4Al8 cuboctahedra, and faces with eight equivalent Ho(2)Al12 cuboctahedra. In the second Ho site, Ho(2) is bonded to three equivalent Al(1) and nine equivalent Al(2) atoms to form HoAl12 cuboctahedra that share corners with six equivalent Al(1)Ho4Al8 cuboctahedra, corners with nine equivalent Ho(2)Al12 cuboctahedra, edges with six equivalent Al(1)Ho4Al8 cuboctahedra, faces with three equivalent Ho(2)Al12 cuboctahedra, faces with three equivalent Al(1)Ho4Al8 cuboctahedra, and faces with four equivalent Ho(1)Al12 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(2) is bonded in a 10-coordinate geometry to one Ho(1), three equivalent Ho(2), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(1) is bonded to two equivalent Ho(1), two equivalent Ho(2), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted AlHo4Al8 cuboctahedra that share corners with four equivalent Ho(2)Al12 cuboctahedra, corners with six equivalent Al(1)Ho4Al8 cuboctahedra, edges with two equivalent Ho(1)Al12 cuboctahedra, edges with four equivalent Ho(2)Al12 cuboctahedra, edges with four equivalent Al(1)Ho4Al8 cuboctahedra, faces with two equivalent Ho(1)Al12 cuboctahedra, faces with two equivalent Ho(2)Al12 cuboctahedra, and faces with four equivalent Al(1)Ho4Al8 cuboctahedra. is represented by the CIF card [CIF]
data_HoAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   7.845
_cell_angle_alpha   67.007
_cell_angle_beta   67.046
_cell_angle_gamma   60.002
_symmetry_Int_Tables_number   1
_cell_volume   227.817
_cell_formula_units_Z   3
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
  Ho  Ho0  1  0.000  0.000  0.000  1.0
  Ho  Ho1  1  0.218  0.218  0.345  1.0
  Ho  Ho2  1  0.782  0.782  0.655  1.0
  Al  Al3  1  0.500  0.500  0.000  1.0
  Al  Al4  1  0.500  0.000  0.000  1.0
  Al  Al5  1  0.000  0.500  0.000  1.0
  Al  Al6  1  0.297  0.297  0.668  1.0
  Al  Al7  1  0.297  0.738  0.668  1.0
  Al  Al8  1  0.738  0.297  0.668  1.0
  Al  Al9  1  0.703  0.703  0.332  1.0
  Al  Al10  1  0.703  0.262  0.332  1.0
  Al  Al11  1  0.262  0.703  0.332  1.0
[/CIF]
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