The material described by Al8Cr4Ho crystallizes in the tetragonal I4/mmm space group. Ho(1) is bonded in a 20-coordinate geometry to eight equivalent Cr(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cr(1) is bonded to two equivalent Ho(1), two equivalent Cr(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted CrHo2Al8Cr2 cuboctahedra that share corners with eight equivalent Al(2)Ho2Al6Cr4 cuboctahedra, corners with ten equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, edges with four equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, edges with four equivalent Al(2)Ho2Al6Cr4 cuboctahedra, faces with six equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, and faces with eight equivalent Al(2)Ho2Al6Cr4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Ho(1), four equivalent Cr(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two equivalent Ho(1), four equivalent Cr(1), two equivalent Al(2), and four equivalent Al(1) atoms to form distorted AlHo2Al6Cr4 cuboctahedra that share corners with eight equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, corners with ten equivalent Al(2)Ho2Al6Cr4 cuboctahedra, edges with three equivalent Al(2)Ho2Al6Cr4 cuboctahedra, edges with four equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, faces with seven equivalent Al(2)Ho2Al6Cr4 cuboctahedra, and faces with eight equivalent Cr(1)Ho2Al8Cr2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho(Al2Cr)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   6.788
_cell_length_c   6.788
_cell_angle_alpha   82.006
_cell_angle_beta   68.104
_cell_angle_gamma   68.104
_symmetry_Int_Tables_number   1
_cell_volume   200.840
_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
  Ho  Ho0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.335  0.665  1.0
  Al  Al2  1  0.000  0.665  0.335  1.0
  Al  Al3  1  0.665  0.335  0.335  1.0
  Al  Al4  1  0.335  0.665  0.665  1.0
  Al  Al5  1  0.500  0.778  0.222  1.0
  Al  Al6  1  0.500  0.222  0.778  1.0
  Al  Al7  1  0.722  0.778  0.778  1.0
  Al  Al8  1  0.278  0.222  0.222  1.0
  Cr  Cr9  1  0.000  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.000  0.500  1.0
  Cr  Cr11  1  0.500  0.500  0.000  1.0
  Cr  Cr12  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by Al8Cr4Ho crystallizes in the tetragonal I4/mmm space group. Ho(1) is bonded in a 20-coordinate geometry to eight equivalent Cr(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cr(1) is bonded to two equivalent Ho(1), two equivalent Cr(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted CrHo2Al8Cr2 cuboctahedra that share corners with eight equivalent Al(2)Ho2Al6Cr4 cuboctahedra, corners with ten equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, edges with four equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, edges with four equivalent Al(2)Ho2Al6Cr4 cuboctahedra, faces with six equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, and faces with eight equivalent Al(2)Ho2Al6Cr4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Ho(1), four equivalent Cr(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two equivalent Ho(1), four equivalent Cr(1), two equivalent Al(2), and four equivalent Al(1) atoms to form distorted AlHo2Al6Cr4 cuboctahedra that share corners with eight equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, corners with ten equivalent Al(2)Ho2Al6Cr4 cuboctahedra, edges with three equivalent Al(2)Ho2Al6Cr4 cuboctahedra, edges with four equivalent Cr(1)Ho2Al8Cr2 cuboctahedra, faces with seven equivalent Al(2)Ho2Al6Cr4 cuboctahedra, and faces with eight equivalent Cr(1)Ho2Al8Cr2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho(Al2Cr)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.063
_cell_length_b   6.788
_cell_length_c   6.788
_cell_angle_alpha   82.006
_cell_angle_beta   68.104
_cell_angle_gamma   68.104
_symmetry_Int_Tables_number   1
_cell_volume   200.840
_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
  Ho  Ho0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.335  0.665  1.0
  Al  Al2  1  0.000  0.665  0.335  1.0
  Al  Al3  1  0.665  0.335  0.335  1.0
  Al  Al4  1  0.335  0.665  0.665  1.0
  Al  Al5  1  0.500  0.778  0.222  1.0
  Al  Al6  1  0.500  0.222  0.778  1.0
  Al  Al7  1  0.722  0.778  0.778  1.0
  Al  Al8  1  0.278  0.222  0.222  1.0
  Cr  Cr9  1  0.000  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.000  0.500  1.0
  Cr  Cr11  1  0.500  0.500  0.000  1.0
  Cr  Cr12  1  0.000  0.500  0.000  1.0
[/CIF]
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