The structure described by Tb2Co17 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 19-coordinate geometry to one Co(4), three equivalent Co(1), six equivalent Co(2), and nine equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Tb(1), two equivalent Co(4), four equivalent Co(2), and four equivalent Co(3) atoms to form CoTb2Co10 cuboctahedra that share corners with four equivalent Co(1)Tb2Co10 cuboctahedra, corners with ten equivalent Co(3)Tb3Co9 cuboctahedra, edges with six equivalent Co(3)Tb3Co9 cuboctahedra, faces with four equivalent Co(1)Tb2Co10 cuboctahedra, and faces with six equivalent Co(3)Tb3Co9 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent Tb(1), two equivalent Co(1), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(3) atoms. In the third Co site, Co(3) is bonded to three equivalent Tb(1), one Co(4), two equivalent Co(1), two equivalent Co(3), and four equivalent Co(2) atoms to form CoTb3Co9 cuboctahedra that share corners with five equivalent Co(1)Tb2Co10 cuboctahedra, corners with ten equivalent Co(3)Tb3Co9 cuboctahedra, edges with three equivalent Co(1)Tb2Co10 cuboctahedra, edges with five equivalent Co(3)Tb3Co9 cuboctahedra, faces with three equivalent Co(1)Tb2Co10 cuboctahedra, and faces with seven equivalent Co(3)Tb3Co9 cuboctahedra. In the fourth Co site, Co(4) is bonded in a 14-coordinate geometry to one Tb(1), one Co(4), three equivalent Co(1), three equivalent Co(3), and six equivalent Co(2) atoms. is represented by the CIF file [CIF]
data_Tb2Co17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.286
_cell_length_b   6.286
_cell_length_c   6.286
_cell_angle_alpha   82.693
_cell_angle_beta   82.693
_cell_angle_gamma   82.693
_symmetry_Int_Tables_number   1
_cell_volume   242.776
_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  0.655  0.655  0.655  1.0
  Tb  Tb1  1  0.345  0.345  0.345  1.0
  Co  Co2  1  0.000  0.000  0.500  1.0
  Co  Co3  1  0.000  0.500  0.000  1.0
  Co  Co4  1  0.500  0.000  0.000  1.0
  Co  Co5  1  0.289  0.711  0.000  1.0
  Co  Co6  1  0.711  0.000  0.289  1.0
  Co  Co7  1  0.000  0.289  0.711  1.0
  Co  Co8  1  0.289  0.000  0.711  1.0
  Co  Co9  1  0.000  0.711  0.289  1.0
  Co  Co10  1  0.711  0.289  0.000  1.0
  Co  Co11  1  0.345  0.345  0.850  1.0
  Co  Co12  1  0.345  0.850  0.345  1.0
  Co  Co13  1  0.850  0.345  0.345  1.0
  Co  Co14  1  0.655  0.655  0.150  1.0
  Co  Co15  1  0.655  0.150  0.655  1.0
  Co  Co16  1  0.150  0.655  0.655  1.0
  Co  Co17  1  0.904  0.904  0.904  1.0
  Co  Co18  1  0.096  0.096  0.096  1.0
[/CIF]
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The structure described by Tb2Co17 crystallizes in the trigonal R-3m space group. Tb(1) is bonded in a 19-coordinate geometry to one Co(4), three equivalent Co(1), six equivalent Co(2), and nine equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Tb(1), two equivalent Co(4), four equivalent Co(2), and four equivalent Co(3) atoms to form CoTb2Co10 cuboctahedra that share corners with four equivalent Co(1)Tb2Co10 cuboctahedra, corners with ten equivalent Co(3)Tb3Co9 cuboctahedra, edges with six equivalent Co(3)Tb3Co9 cuboctahedra, faces with four equivalent Co(1)Tb2Co10 cuboctahedra, and faces with six equivalent Co(3)Tb3Co9 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent Tb(1), two equivalent Co(1), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(3) atoms. In the third Co site, Co(3) is bonded to three equivalent Tb(1), one Co(4), two equivalent Co(1), two equivalent Co(3), and four equivalent Co(2) atoms to form CoTb3Co9 cuboctahedra that share corners with five equivalent Co(1)Tb2Co10 cuboctahedra, corners with ten equivalent Co(3)Tb3Co9 cuboctahedra, edges with three equivalent Co(1)Tb2Co10 cuboctahedra, edges with five equivalent Co(3)Tb3Co9 cuboctahedra, faces with three equivalent Co(1)Tb2Co10 cuboctahedra, and faces with seven equivalent Co(3)Tb3Co9 cuboctahedra. In the fourth Co site, Co(4) is bonded in a 14-coordinate geometry to one Tb(1), one Co(4), three equivalent Co(1), three equivalent Co(3), and six equivalent Co(2) atoms. is represented by the CIF file [CIF]
data_Tb2Co17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.286
_cell_length_b   6.286
_cell_length_c   6.286
_cell_angle_alpha   82.693
_cell_angle_beta   82.693
_cell_angle_gamma   82.693
_symmetry_Int_Tables_number   1
_cell_volume   242.776
_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  0.655  0.655  0.655  1.0
  Tb  Tb1  1  0.345  0.345  0.345  1.0
  Co  Co2  1  0.000  0.000  0.500  1.0
  Co  Co3  1  0.000  0.500  0.000  1.0
  Co  Co4  1  0.500  0.000  0.000  1.0
  Co  Co5  1  0.289  0.711  0.000  1.0
  Co  Co6  1  0.711  0.000  0.289  1.0
  Co  Co7  1  0.000  0.289  0.711  1.0
  Co  Co8  1  0.289  0.000  0.711  1.0
  Co  Co9  1  0.000  0.711  0.289  1.0
  Co  Co10  1  0.711  0.289  0.000  1.0
  Co  Co11  1  0.345  0.345  0.850  1.0
  Co  Co12  1  0.345  0.850  0.345  1.0
  Co  Co13  1  0.850  0.345  0.345  1.0
  Co  Co14  1  0.655  0.655  0.150  1.0
  Co  Co15  1  0.655  0.150  0.655  1.0
  Co  Co16  1  0.150  0.655  0.655  1.0
  Co  Co17  1  0.904  0.904  0.904  1.0
  Co  Co18  1  0.096  0.096  0.096  1.0
[/CIF]
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