The compound described by Tb2CoAl3 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 12-coordinate geometry to three equivalent Co(1) and nine equivalent Al(1) atoms. Co(1) is bonded to six equivalent Tb(1) and six equivalent Al(1) atoms to form CoTb6Al6 cuboctahedra that share corners with six equivalent Co(1)Tb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Tb6Al4Co2 cuboctahedra, edges with six equivalent Co(1)Tb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Tb6Al4Co2 cuboctahedra. Al(1) is bonded to six equivalent Tb(1), two equivalent Co(1), and four equivalent Al(1) atoms to form distorted AlTb6Al4Co2 cuboctahedra that share corners with four equivalent Co(1)Tb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Tb6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Tb6Al4Co2 cuboctahedra, faces with six equivalent Co(1)Tb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Tb6Al4Co2 cuboctahedra. is represented by the CIF file [CIF]
data_Tb2Al3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.372
_cell_length_b   5.372
_cell_length_c   5.372
_cell_angle_alpha   61.516
_cell_angle_beta   61.516
_cell_angle_gamma   61.516
_symmetry_Int_Tables_number   1
_cell_volume   113.348
_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  0.626  0.626  0.626  1.0
  Tb  Tb1  1  0.374  0.374  0.374  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Tb2CoAl3 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 12-coordinate geometry to three equivalent Co(1) and nine equivalent Al(1) atoms. Co(1) is bonded to six equivalent Tb(1) and six equivalent Al(1) atoms to form CoTb6Al6 cuboctahedra that share corners with six equivalent Co(1)Tb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Tb6Al4Co2 cuboctahedra, edges with six equivalent Co(1)Tb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Tb6Al4Co2 cuboctahedra. Al(1) is bonded to six equivalent Tb(1), two equivalent Co(1), and four equivalent Al(1) atoms to form distorted AlTb6Al4Co2 cuboctahedra that share corners with four equivalent Co(1)Tb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Tb6Al4Co2 cuboctahedra, edges with six equivalent Al(1)Tb6Al4Co2 cuboctahedra, faces with six equivalent Co(1)Tb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Tb6Al4Co2 cuboctahedra. is represented by the CIF file [CIF]
data_Tb2Al3Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.372
_cell_length_b   5.372
_cell_length_c   5.372
_cell_angle_alpha   61.516
_cell_angle_beta   61.516
_cell_angle_gamma   61.516
_symmetry_Int_Tables_number   1
_cell_volume   113.348
_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  0.626  0.626  0.626  1.0
  Tb  Tb1  1  0.374  0.374  0.374  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Co  Co5  1  0.000  0.000  0.000  1.0
[/CIF]
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