The crystal structure described by Yb3Ta is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to four equivalent Yb(1), four equivalent Yb(2), and four equivalent Ta(1) atoms to form distorted YbYb8Ta4 cuboctahedra that share corners with twelve equivalent Yb(1)Yb8Ta4 cuboctahedra, edges with eight equivalent Yb(1)Yb8Ta4 cuboctahedra, edges with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with eight equivalent Ta(1)Yb12 cuboctahedra, faces with four equivalent Yb(2)Yb8Ta4 cuboctahedra, faces with four equivalent Ta(1)Yb12 cuboctahedra, and faces with ten equivalent Yb(1)Yb8Ta4 cuboctahedra. In the second Yb site, Yb(2) is bonded to eight equivalent Yb(1) and four equivalent Ta(1) atoms to form YbYb8Ta4 cuboctahedra that share corners with four equivalent Yb(2)Yb8Ta4 cuboctahedra, corners with eight equivalent Ta(1)Yb12 cuboctahedra, edges with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with sixteen equivalent Yb(1)Yb8Ta4 cuboctahedra, faces with four equivalent Yb(2)Yb8Ta4 cuboctahedra, faces with six equivalent Ta(1)Yb12 cuboctahedra, and faces with eight equivalent Yb(1)Yb8Ta4 cuboctahedra. Ta(1) is bonded to four equivalent Yb(2) and eight equivalent Yb(1) atoms to form TaYb12 cuboctahedra that share corners with four equivalent Ta(1)Yb12 cuboctahedra, corners with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with eight equivalent Ta(1)Yb12 cuboctahedra, edges with sixteen equivalent Yb(1)Yb8Ta4 cuboctahedra, faces with four equivalent Ta(1)Yb12 cuboctahedra, faces with six equivalent Yb(2)Yb8Ta4 cuboctahedra, and faces with eight equivalent Yb(1)Yb8Ta4 cuboctahedra. is represented by the CIF file [CIF]
data_Yb3Ta
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   5.959
_cell_length_c   5.959
_cell_angle_alpha   131.110
_cell_angle_beta   131.110
_cell_angle_gamma   71.638
_symmetry_Int_Tables_number   1
_cell_volume   117.558
_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
  Yb  Yb0  1  0.750  0.250  0.500  1.0
  Yb  Yb1  1  0.250  0.750  0.500  1.0
  Yb  Yb2  1  0.500  0.500  0.000  1.0
  Ta  Ta3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Yb3Ta is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to four equivalent Yb(1), four equivalent Yb(2), and four equivalent Ta(1) atoms to form distorted YbYb8Ta4 cuboctahedra that share corners with twelve equivalent Yb(1)Yb8Ta4 cuboctahedra, edges with eight equivalent Yb(1)Yb8Ta4 cuboctahedra, edges with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with eight equivalent Ta(1)Yb12 cuboctahedra, faces with four equivalent Yb(2)Yb8Ta4 cuboctahedra, faces with four equivalent Ta(1)Yb12 cuboctahedra, and faces with ten equivalent Yb(1)Yb8Ta4 cuboctahedra. In the second Yb site, Yb(2) is bonded to eight equivalent Yb(1) and four equivalent Ta(1) atoms to form YbYb8Ta4 cuboctahedra that share corners with four equivalent Yb(2)Yb8Ta4 cuboctahedra, corners with eight equivalent Ta(1)Yb12 cuboctahedra, edges with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with sixteen equivalent Yb(1)Yb8Ta4 cuboctahedra, faces with four equivalent Yb(2)Yb8Ta4 cuboctahedra, faces with six equivalent Ta(1)Yb12 cuboctahedra, and faces with eight equivalent Yb(1)Yb8Ta4 cuboctahedra. Ta(1) is bonded to four equivalent Yb(2) and eight equivalent Yb(1) atoms to form TaYb12 cuboctahedra that share corners with four equivalent Ta(1)Yb12 cuboctahedra, corners with eight equivalent Yb(2)Yb8Ta4 cuboctahedra, edges with eight equivalent Ta(1)Yb12 cuboctahedra, edges with sixteen equivalent Yb(1)Yb8Ta4 cuboctahedra, faces with four equivalent Ta(1)Yb12 cuboctahedra, faces with six equivalent Yb(2)Yb8Ta4 cuboctahedra, and faces with eight equivalent Yb(1)Yb8Ta4 cuboctahedra. is represented by the CIF file [CIF]
data_Yb3Ta
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   5.959
_cell_length_c   5.959
_cell_angle_alpha   131.110
_cell_angle_beta   131.110
_cell_angle_gamma   71.638
_symmetry_Int_Tables_number   1
_cell_volume   117.558
_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
  Yb  Yb0  1  0.750  0.250  0.500  1.0
  Yb  Yb1  1  0.250  0.750  0.500  1.0
  Yb  Yb2  1  0.500  0.500  0.000  1.0
  Ta  Ta3  1  0.000  0.000  0.000  1.0
[/CIF]
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