The structure described by CaTb3 crystallizes in the tetragonal I4/mmm space group. Ca(1) is bonded to four equivalent Tb(2) and eight equivalent Tb(1) atoms to form CaTb12 cuboctahedra that share corners with four equivalent Ca(1)Tb12 cuboctahedra, corners with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, edges with eight equivalent Ca(1)Tb12 cuboctahedra, edges with sixteen equivalent Tb(1)Ca4Tb8 cuboctahedra, faces with four equivalent Ca(1)Tb12 cuboctahedra, faces with six equivalent Tb(2)Ca4Tb8 cuboctahedra, and faces with eight equivalent Tb(1)Ca4Tb8 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to four equivalent Ca(1), four equivalent Tb(1), and four equivalent Tb(2) atoms to form TbCa4Tb8 cuboctahedra that share corners with twelve equivalent Tb(1)Ca4Tb8 cuboctahedra, edges with eight equivalent Ca(1)Tb12 cuboctahedra, edges with eight equivalent Tb(1)Ca4Tb8 cuboctahedra, edges with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, faces with four equivalent Ca(1)Tb12 cuboctahedra, faces with four equivalent Tb(2)Ca4Tb8 cuboctahedra, and faces with ten equivalent Tb(1)Ca4Tb8 cuboctahedra. In the second Tb site, Tb(2) is bonded to four equivalent Ca(1) and eight equivalent Tb(1) atoms to form TbCa4Tb8 cuboctahedra that share corners with four equivalent Tb(2)Ca4Tb8 cuboctahedra, corners with eight equivalent Ca(1)Tb12 cuboctahedra, edges with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, edges with sixteen equivalent Tb(1)Ca4Tb8 cuboctahedra, faces with four equivalent Tb(2)Ca4Tb8 cuboctahedra, faces with six equivalent Ca(1)Tb12 cuboctahedra, and faces with eight equivalent Tb(1)Ca4Tb8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaTb3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.251
_cell_length_b   6.251
_cell_length_c   6.251
_cell_angle_alpha   131.659
_cell_angle_beta   131.659
_cell_angle_gamma   70.768
_symmetry_Int_Tables_number   1
_cell_volume   133.576
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Tb  Tb1  1  0.750  0.250  0.500  1.0
  Tb  Tb2  1  0.250  0.750  0.500  1.0
  Tb  Tb3  1  0.500  0.500  0.000  1.0
[/CIF]
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The structure described by CaTb3 crystallizes in the tetragonal I4/mmm space group. Ca(1) is bonded to four equivalent Tb(2) and eight equivalent Tb(1) atoms to form CaTb12 cuboctahedra that share corners with four equivalent Ca(1)Tb12 cuboctahedra, corners with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, edges with eight equivalent Ca(1)Tb12 cuboctahedra, edges with sixteen equivalent Tb(1)Ca4Tb8 cuboctahedra, faces with four equivalent Ca(1)Tb12 cuboctahedra, faces with six equivalent Tb(2)Ca4Tb8 cuboctahedra, and faces with eight equivalent Tb(1)Ca4Tb8 cuboctahedra. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to four equivalent Ca(1), four equivalent Tb(1), and four equivalent Tb(2) atoms to form TbCa4Tb8 cuboctahedra that share corners with twelve equivalent Tb(1)Ca4Tb8 cuboctahedra, edges with eight equivalent Ca(1)Tb12 cuboctahedra, edges with eight equivalent Tb(1)Ca4Tb8 cuboctahedra, edges with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, faces with four equivalent Ca(1)Tb12 cuboctahedra, faces with four equivalent Tb(2)Ca4Tb8 cuboctahedra, and faces with ten equivalent Tb(1)Ca4Tb8 cuboctahedra. In the second Tb site, Tb(2) is bonded to four equivalent Ca(1) and eight equivalent Tb(1) atoms to form TbCa4Tb8 cuboctahedra that share corners with four equivalent Tb(2)Ca4Tb8 cuboctahedra, corners with eight equivalent Ca(1)Tb12 cuboctahedra, edges with eight equivalent Tb(2)Ca4Tb8 cuboctahedra, edges with sixteen equivalent Tb(1)Ca4Tb8 cuboctahedra, faces with four equivalent Tb(2)Ca4Tb8 cuboctahedra, faces with six equivalent Ca(1)Tb12 cuboctahedra, and faces with eight equivalent Tb(1)Ca4Tb8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaTb3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.251
_cell_length_b   6.251
_cell_length_c   6.251
_cell_angle_alpha   131.659
_cell_angle_beta   131.659
_cell_angle_gamma   70.768
_symmetry_Int_Tables_number   1
_cell_volume   133.576
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Tb  Tb1  1  0.750  0.250  0.500  1.0
  Tb  Tb2  1  0.250  0.750  0.500  1.0
  Tb  Tb3  1  0.500  0.500  0.000  1.0
[/CIF]
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