The crystal structure described by U3Tb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Tb(1) atoms to form UTb4U8 cuboctahedra that share corners with twelve equivalent U(1)Tb4U8 cuboctahedra, edges with eight equivalent U(1)Tb4U8 cuboctahedra, edges with eight equivalent U(2)Tb4U8 cuboctahedra, edges with eight equivalent Tb(1)U12 cuboctahedra, faces with four equivalent U(2)Tb4U8 cuboctahedra, faces with four equivalent Tb(1)U12 cuboctahedra, and faces with ten equivalent U(1)Tb4U8 cuboctahedra. In the second U site, U(2) is bonded to eight equivalent U(1) and four equivalent Tb(1) atoms to form distorted UTb4U8 cuboctahedra that share corners with four equivalent U(2)Tb4U8 cuboctahedra, corners with eight equivalent Tb(1)U12 cuboctahedra, edges with eight equivalent U(2)Tb4U8 cuboctahedra, edges with sixteen equivalent U(1)Tb4U8 cuboctahedra, faces with four equivalent U(2)Tb4U8 cuboctahedra, faces with six equivalent Tb(1)U12 cuboctahedra, and faces with eight equivalent U(1)Tb4U8 cuboctahedra. Tb(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form TbU12 cuboctahedra that share corners with four equivalent Tb(1)U12 cuboctahedra, corners with eight equivalent U(2)Tb4U8 cuboctahedra, edges with eight equivalent Tb(1)U12 cuboctahedra, edges with sixteen equivalent U(1)Tb4U8 cuboctahedra, faces with four equivalent Tb(1)U12 cuboctahedra, faces with six equivalent U(2)Tb4U8 cuboctahedra, and faces with eight equivalent U(1)Tb4U8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TbU3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.675
_cell_length_b   5.675
_cell_length_c   5.675
_cell_angle_alpha   134.225
_cell_angle_beta   134.225
_cell_angle_gamma   66.738
_symmetry_Int_Tables_number   1
_cell_volume   92.335
_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
  U  U1  1  0.750  0.250  0.500  1.0
  U  U2  1  0.250  0.750  0.500  1.0
  U  U3  1  0.500  0.500  0.000  1.0
[/CIF]
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The crystal structure described by U3Tb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Tb(1) atoms to form UTb4U8 cuboctahedra that share corners with twelve equivalent U(1)Tb4U8 cuboctahedra, edges with eight equivalent U(1)Tb4U8 cuboctahedra, edges with eight equivalent U(2)Tb4U8 cuboctahedra, edges with eight equivalent Tb(1)U12 cuboctahedra, faces with four equivalent U(2)Tb4U8 cuboctahedra, faces with four equivalent Tb(1)U12 cuboctahedra, and faces with ten equivalent U(1)Tb4U8 cuboctahedra. In the second U site, U(2) is bonded to eight equivalent U(1) and four equivalent Tb(1) atoms to form distorted UTb4U8 cuboctahedra that share corners with four equivalent U(2)Tb4U8 cuboctahedra, corners with eight equivalent Tb(1)U12 cuboctahedra, edges with eight equivalent U(2)Tb4U8 cuboctahedra, edges with sixteen equivalent U(1)Tb4U8 cuboctahedra, faces with four equivalent U(2)Tb4U8 cuboctahedra, faces with six equivalent Tb(1)U12 cuboctahedra, and faces with eight equivalent U(1)Tb4U8 cuboctahedra. Tb(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form TbU12 cuboctahedra that share corners with four equivalent Tb(1)U12 cuboctahedra, corners with eight equivalent U(2)Tb4U8 cuboctahedra, edges with eight equivalent Tb(1)U12 cuboctahedra, edges with sixteen equivalent U(1)Tb4U8 cuboctahedra, faces with four equivalent Tb(1)U12 cuboctahedra, faces with six equivalent U(2)Tb4U8 cuboctahedra, and faces with eight equivalent U(1)Tb4U8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TbU3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.675
_cell_length_b   5.675
_cell_length_c   5.675
_cell_angle_alpha   134.225
_cell_angle_beta   134.225
_cell_angle_gamma   66.738
_symmetry_Int_Tables_number   1
_cell_volume   92.335
_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
  U  U1  1  0.750  0.250  0.500  1.0
  U  U2  1  0.250  0.750  0.500  1.0
  U  U3  1  0.500  0.500  0.000  1.0
[/CIF]
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