The material described by Ho3Tb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Ho(1), four equivalent Ho(2), and four equivalent Tb(1) atoms to form HoTb4Ho8 cuboctahedra that share corners with twelve equivalent Ho(1)Tb4Ho8 cuboctahedra, edges with eight equivalent Ho(1)Tb4Ho8 cuboctahedra, edges with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with eight equivalent Tb(1)Ho12 cuboctahedra, faces with four equivalent Ho(2)Tb4Ho8 cuboctahedra, faces with four equivalent Tb(1)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Tb4Ho8 cuboctahedra. In the second Ho site, Ho(2) is bonded to eight equivalent Ho(1) and four equivalent Tb(1) atoms to form HoTb4Ho8 cuboctahedra that share corners with four equivalent Ho(2)Tb4Ho8 cuboctahedra, corners with eight equivalent Tb(1)Ho12 cuboctahedra, edges with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with sixteen equivalent Ho(1)Tb4Ho8 cuboctahedra, faces with four equivalent Ho(2)Tb4Ho8 cuboctahedra, faces with six equivalent Tb(1)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Tb4Ho8 cuboctahedra. Tb(1) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form TbHo12 cuboctahedra that share corners with four equivalent Tb(1)Ho12 cuboctahedra, corners with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with eight equivalent Tb(1)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Tb4Ho8 cuboctahedra, faces with four equivalent Tb(1)Ho12 cuboctahedra, faces with six equivalent Ho(2)Tb4Ho8 cuboctahedra, and faces with eight equivalent Ho(1)Tb4Ho8 cuboctahedra. is represented by the CIF file [CIF]
data_TbHo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   6.129
_cell_angle_alpha   131.875
_cell_angle_beta   131.875
_cell_angle_gamma   70.427
_symmetry_Int_Tables_number   1
_cell_volume   125.112
_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  0.000  0.000  0.000  1.0
  Ho  Ho1  1  0.750  0.250  0.500  1.0
  Ho  Ho2  1  0.250  0.750  0.500  1.0
  Ho  Ho3  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by Ho3Tb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Ho(1), four equivalent Ho(2), and four equivalent Tb(1) atoms to form HoTb4Ho8 cuboctahedra that share corners with twelve equivalent Ho(1)Tb4Ho8 cuboctahedra, edges with eight equivalent Ho(1)Tb4Ho8 cuboctahedra, edges with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with eight equivalent Tb(1)Ho12 cuboctahedra, faces with four equivalent Ho(2)Tb4Ho8 cuboctahedra, faces with four equivalent Tb(1)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Tb4Ho8 cuboctahedra. In the second Ho site, Ho(2) is bonded to eight equivalent Ho(1) and four equivalent Tb(1) atoms to form HoTb4Ho8 cuboctahedra that share corners with four equivalent Ho(2)Tb4Ho8 cuboctahedra, corners with eight equivalent Tb(1)Ho12 cuboctahedra, edges with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with sixteen equivalent Ho(1)Tb4Ho8 cuboctahedra, faces with four equivalent Ho(2)Tb4Ho8 cuboctahedra, faces with six equivalent Tb(1)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Tb4Ho8 cuboctahedra. Tb(1) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form TbHo12 cuboctahedra that share corners with four equivalent Tb(1)Ho12 cuboctahedra, corners with eight equivalent Ho(2)Tb4Ho8 cuboctahedra, edges with eight equivalent Tb(1)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Tb4Ho8 cuboctahedra, faces with four equivalent Tb(1)Ho12 cuboctahedra, faces with six equivalent Ho(2)Tb4Ho8 cuboctahedra, and faces with eight equivalent Ho(1)Tb4Ho8 cuboctahedra. is represented by the CIF file [CIF]
data_TbHo3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   6.129
_cell_angle_alpha   131.875
_cell_angle_beta   131.875
_cell_angle_gamma   70.427
_symmetry_Int_Tables_number   1
_cell_volume   125.112
_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  0.000  0.000  0.000  1.0
  Ho  Ho1  1  0.750  0.250  0.500  1.0
  Ho  Ho2  1  0.250  0.750  0.500  1.0
  Ho  Ho3  1  0.500  0.500  0.000  1.0
[/CIF]
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