The crystal structure described by TmTb3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Tm(1) is bonded to four equivalent Tb(2) and eight equivalent Tb(1) atoms to form TmTb12 cuboctahedra that share corners with four equivalent Tm(1)Tb12 cuboctahedra, corners with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, edges with eight equivalent Tm(1)Tb12 cuboctahedra, edges with sixteen equivalent Tb(1)Tb8Tm4 cuboctahedra, faces with four equivalent Tm(1)Tb12 cuboctahedra, faces with six equivalent Tb(2)Tb8Tm4 cuboctahedra, and faces with eight equivalent Tb(1)Tb8Tm4 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to four equivalent Tm(1), four equivalent Tb(1), and four equivalent Tb(2) atoms to form TbTb8Tm4 cuboctahedra that share corners with twelve equivalent Tb(1)Tb8Tm4 cuboctahedra, edges with eight equivalent Tm(1)Tb12 cuboctahedra, edges with eight equivalent Tb(1)Tb8Tm4 cuboctahedra, edges with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, faces with four equivalent Tm(1)Tb12 cuboctahedra, faces with four equivalent Tb(2)Tb8Tm4 cuboctahedra, and faces with ten equivalent Tb(1)Tb8Tm4 cuboctahedra. In the second Tb site, Tb(2) is bonded to four equivalent Tm(1) and eight equivalent Tb(1) atoms to form TbTb8Tm4 cuboctahedra that share corners with four equivalent Tb(2)Tb8Tm4 cuboctahedra, corners with eight equivalent Tm(1)Tb12 cuboctahedra, edges with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, edges with sixteen equivalent Tb(1)Tb8Tm4 cuboctahedra, faces with four equivalent Tb(2)Tb8Tm4 cuboctahedra, faces with six equivalent Tm(1)Tb12 cuboctahedra, and faces with eight equivalent Tb(1)Tb8Tm4 cuboctahedra. is represented by the CIF card [CIF]
data_Tb3Tm
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.143
_cell_length_b   6.143
_cell_length_c   6.143
_cell_angle_alpha   131.839
_cell_angle_beta   131.839
_cell_angle_gamma   70.483
_symmetry_Int_Tables_number   1
_cell_volume   126.095
_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  0.750  0.250  0.500  1.0
  Tb  Tb1  1  0.250  0.750  0.500  1.0
  Tb  Tb2  1  0.500  0.500  0.000  1.0
  Tm  Tm3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by TmTb3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Tm(1) is bonded to four equivalent Tb(2) and eight equivalent Tb(1) atoms to form TmTb12 cuboctahedra that share corners with four equivalent Tm(1)Tb12 cuboctahedra, corners with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, edges with eight equivalent Tm(1)Tb12 cuboctahedra, edges with sixteen equivalent Tb(1)Tb8Tm4 cuboctahedra, faces with four equivalent Tm(1)Tb12 cuboctahedra, faces with six equivalent Tb(2)Tb8Tm4 cuboctahedra, and faces with eight equivalent Tb(1)Tb8Tm4 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to four equivalent Tm(1), four equivalent Tb(1), and four equivalent Tb(2) atoms to form TbTb8Tm4 cuboctahedra that share corners with twelve equivalent Tb(1)Tb8Tm4 cuboctahedra, edges with eight equivalent Tm(1)Tb12 cuboctahedra, edges with eight equivalent Tb(1)Tb8Tm4 cuboctahedra, edges with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, faces with four equivalent Tm(1)Tb12 cuboctahedra, faces with four equivalent Tb(2)Tb8Tm4 cuboctahedra, and faces with ten equivalent Tb(1)Tb8Tm4 cuboctahedra. In the second Tb site, Tb(2) is bonded to four equivalent Tm(1) and eight equivalent Tb(1) atoms to form TbTb8Tm4 cuboctahedra that share corners with four equivalent Tb(2)Tb8Tm4 cuboctahedra, corners with eight equivalent Tm(1)Tb12 cuboctahedra, edges with eight equivalent Tb(2)Tb8Tm4 cuboctahedra, edges with sixteen equivalent Tb(1)Tb8Tm4 cuboctahedra, faces with four equivalent Tb(2)Tb8Tm4 cuboctahedra, faces with six equivalent Tm(1)Tb12 cuboctahedra, and faces with eight equivalent Tb(1)Tb8Tm4 cuboctahedra. is represented by the CIF card [CIF]
data_Tb3Tm
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.143
_cell_length_b   6.143
_cell_length_c   6.143
_cell_angle_alpha   131.839
_cell_angle_beta   131.839
_cell_angle_gamma   70.483
_symmetry_Int_Tables_number   1
_cell_volume   126.095
_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  0.750  0.250  0.500  1.0
  Tb  Tb1  1  0.250  0.750  0.500  1.0
  Tb  Tb2  1  0.500  0.500  0.000  1.0
  Tm  Tm3  1  0.000  0.000  0.000  1.0
[/CIF]
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