The compound described by Tb4HfAl15 crystallizes in the trigonal R-3m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to three equivalent Al(3) and nine equivalent Al(2) atoms to form TbAl12 cuboctahedra that share corners with three equivalent Tb(2)Al12 cuboctahedra, corners with six equivalent Tb(1)Al12 cuboctahedra, corners with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra,  a faceface with one Hf(1)Al12 cuboctahedra, faces with three equivalent Tb(1)Al12 cuboctahedra, and faces with three equivalent Tb(2)Al12 cuboctahedra. In the second Tb site, Tb(2) is bonded to three equivalent Al(1), three equivalent Al(2), and six equivalent Al(3) atoms to form TbAl12 cuboctahedra that share corners with three equivalent Tb(1)Al12 cuboctahedra, corners with nine equivalent Tb(2)Al12 cuboctahedra, edges with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with three equivalent Tb(1)Al12 cuboctahedra, faces with three equivalent Hf(1)Al12 cuboctahedra, and faces with three equivalent Al(1)Tb2Hf2Al8 cuboctahedra. Hf(1) is bonded to six equivalent Al(1) and six equivalent Al(3) atoms to form HfAl12 cuboctahedra that share corners with six equivalent Hf(1)Al12 cuboctahedra, edges with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with two equivalent Tb(1)Al12 cuboctahedra, faces with six equivalent Tb(2)Al12 cuboctahedra, and faces with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Tb(2), two equivalent Hf(1), four equivalent Al(1), and four equivalent Al(3) atoms to form distorted AlTb2Hf2Al8 cuboctahedra that share corners with four equivalent Tb(1)Al12 cuboctahedra, corners with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, edges with two equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Tb(2)Al12 cuboctahedra, edges with four equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with two equivalent Tb(2)Al12 cuboctahedra, faces with two equivalent Hf(1)Al12 cuboctahedra, and faces with four equivalent Al(1)Tb2Hf2Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a distorted square co-planar geometry to one Tb(2), three equivalent Tb(1), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Tb(1), two equivalent Tb(2), one Hf(1), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4HfAl15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.506
_cell_length_b   12.506
_cell_length_c   12.506
_cell_angle_alpha   28.001
_cell_angle_beta   28.001
_cell_angle_gamma   28.001
_symmetry_Int_Tables_number   1
_cell_volume   380.767
_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
  Tb  Tb0  1  0.869  0.869  0.869  1.0
  Tb  Tb1  1  0.131  0.131  0.131  1.0
  Tb  Tb2  1  0.600  0.600  0.600  1.0
  Tb  Tb3  1  0.400  0.400  0.400  1.0
  Hf  Hf4  1  0.000  0.000  0.000  1.0
  Al  Al5  1  0.500  0.500  0.000  1.0
  Al  Al6  1  0.000  0.500  0.500  1.0
  Al  Al7  1  0.500  0.000  0.500  1.0
  Al  Al8  1  0.364  0.872  0.364  1.0
  Al  Al9  1  0.364  0.364  0.872  1.0
  Al  Al10  1  0.872  0.364  0.364  1.0
  Al  Al11  1  0.636  0.128  0.636  1.0
  Al  Al12  1  0.636  0.636  0.128  1.0
  Al  Al13  1  0.128  0.636  0.636  1.0
  Al  Al14  1  0.116  0.575  0.116  1.0
  Al  Al15  1  0.116  0.116  0.575  1.0
  Al  Al16  1  0.575  0.116  0.116  1.0
  Al  Al17  1  0.884  0.425  0.884  1.0
  Al  Al18  1  0.884  0.884  0.425  1.0
  Al  Al19  1  0.425  0.884  0.884  1.0
[/CIF]
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The compound described by Tb4HfAl15 crystallizes in the trigonal R-3m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to three equivalent Al(3) and nine equivalent Al(2) atoms to form TbAl12 cuboctahedra that share corners with three equivalent Tb(2)Al12 cuboctahedra, corners with six equivalent Tb(1)Al12 cuboctahedra, corners with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra,  a faceface with one Hf(1)Al12 cuboctahedra, faces with three equivalent Tb(1)Al12 cuboctahedra, and faces with three equivalent Tb(2)Al12 cuboctahedra. In the second Tb site, Tb(2) is bonded to three equivalent Al(1), three equivalent Al(2), and six equivalent Al(3) atoms to form TbAl12 cuboctahedra that share corners with three equivalent Tb(1)Al12 cuboctahedra, corners with nine equivalent Tb(2)Al12 cuboctahedra, edges with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with three equivalent Tb(1)Al12 cuboctahedra, faces with three equivalent Hf(1)Al12 cuboctahedra, and faces with three equivalent Al(1)Tb2Hf2Al8 cuboctahedra. Hf(1) is bonded to six equivalent Al(1) and six equivalent Al(3) atoms to form HfAl12 cuboctahedra that share corners with six equivalent Hf(1)Al12 cuboctahedra, edges with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with two equivalent Tb(1)Al12 cuboctahedra, faces with six equivalent Tb(2)Al12 cuboctahedra, and faces with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Tb(2), two equivalent Hf(1), four equivalent Al(1), and four equivalent Al(3) atoms to form distorted AlTb2Hf2Al8 cuboctahedra that share corners with four equivalent Tb(1)Al12 cuboctahedra, corners with six equivalent Al(1)Tb2Hf2Al8 cuboctahedra, edges with two equivalent Hf(1)Al12 cuboctahedra, edges with four equivalent Tb(2)Al12 cuboctahedra, edges with four equivalent Al(1)Tb2Hf2Al8 cuboctahedra, faces with two equivalent Tb(2)Al12 cuboctahedra, faces with two equivalent Hf(1)Al12 cuboctahedra, and faces with four equivalent Al(1)Tb2Hf2Al8 cuboctahedra. In the second Al site, Al(2) is bonded in a distorted square co-planar geometry to one Tb(2), three equivalent Tb(1), and two equivalent Al(3) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Tb(1), two equivalent Tb(2), one Hf(1), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4HfAl15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.506
_cell_length_b   12.506
_cell_length_c   12.506
_cell_angle_alpha   28.001
_cell_angle_beta   28.001
_cell_angle_gamma   28.001
_symmetry_Int_Tables_number   1
_cell_volume   380.767
_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
  Tb  Tb0  1  0.869  0.869  0.869  1.0
  Tb  Tb1  1  0.131  0.131  0.131  1.0
  Tb  Tb2  1  0.600  0.600  0.600  1.0
  Tb  Tb3  1  0.400  0.400  0.400  1.0
  Hf  Hf4  1  0.000  0.000  0.000  1.0
  Al  Al5  1  0.500  0.500  0.000  1.0
  Al  Al6  1  0.000  0.500  0.500  1.0
  Al  Al7  1  0.500  0.000  0.500  1.0
  Al  Al8  1  0.364  0.872  0.364  1.0
  Al  Al9  1  0.364  0.364  0.872  1.0
  Al  Al10  1  0.872  0.364  0.364  1.0
  Al  Al11  1  0.636  0.128  0.636  1.0
  Al  Al12  1  0.636  0.636  0.128  1.0
  Al  Al13  1  0.128  0.636  0.636  1.0
  Al  Al14  1  0.116  0.575  0.116  1.0
  Al  Al15  1  0.116  0.116  0.575  1.0
  Al  Al16  1  0.575  0.116  0.116  1.0
  Al  Al17  1  0.884  0.425  0.884  1.0
  Al  Al18  1  0.884  0.884  0.425  1.0
  Al  Al19  1  0.425  0.884  0.884  1.0
[/CIF]
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