The material described by TbNdFe17 crystallizes in the trigonal R3m space group. Tb(1) is bonded in a 19-coordinate geometry to one Fe(6), three equivalent Fe(2), three equivalent Fe(4), six equivalent Fe(1), and six equivalent Fe(3) atoms. Nd(1) is bonded in a 19-coordinate geometry to one Fe(5), three equivalent Fe(1), three equivalent Fe(4), six equivalent Fe(2), and six equivalent Fe(3) atoms. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Tb(1), one Nd(1), one Fe(6), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeTb2NdFe9 cuboctahedra that share corners with two equivalent Fe(1)Tb2NdFe9 cuboctahedra, corners with five equivalent Fe(4)TbNdFe10 cuboctahedra, corners with eight equivalent Fe(2)TbNd2Fe9 cuboctahedra,  an edgeedge with one Fe(2)TbNd2Fe9 cuboctahedra, edges with three equivalent Fe(4)TbNdFe10 cuboctahedra, edges with four equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(4)TbNdFe10 cuboctahedra, and faces with four equivalent Fe(1)Tb2NdFe9 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Tb(1), two equivalent Nd(1), one Fe(5), two equivalent Fe(1), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeTbNd2Fe9 cuboctahedra that share corners with two equivalent Fe(2)TbNd2Fe9 cuboctahedra, corners with five equivalent Fe(4)TbNdFe10 cuboctahedra, corners with eight equivalent Fe(1)Tb2NdFe9 cuboctahedra,  an edgeedge with one Fe(1)Tb2NdFe9 cuboctahedra, edges with three equivalent Fe(4)TbNdFe10 cuboctahedra, edges with four equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(4)TbNdFe10 cuboctahedra, and faces with four equivalent Fe(2)TbNd2Fe9 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Tb(1), one Nd(1), one Fe(5), one Fe(6), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Fe(4) atoms. In the fourth Fe site, Fe(4) is bonded to one Tb(1), one Nd(1), one Fe(5), one Fe(6), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form FeTbNdFe10 cuboctahedra that share corners with four equivalent Fe(4)TbNdFe10 cuboctahedra, corners with five equivalent Fe(1)Tb2NdFe9 cuboctahedra, corners with five equivalent Fe(2)TbNd2Fe9 cuboctahedra, edges with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, edges with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, and faces with four equivalent Fe(4)TbNdFe10 cuboctahedra. In the fifth Fe site, Fe(5) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(6), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(3) atoms. In the sixth Fe site, Fe(6) is bonded in a 14-coordinate geometry to one Tb(1), one Fe(5), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_TbNdFe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.377
_cell_length_b   6.377
_cell_length_c   6.377
_cell_angle_alpha   82.556
_cell_angle_beta   82.556
_cell_angle_gamma   82.556
_symmetry_Int_Tables_number   1
_cell_volume   253.243
_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  0.343  0.343  0.343  1.0
  Nd  Nd1  1  0.656  0.656  0.656  1.0
  Fe  Fe2  1  0.339  0.339  0.847  1.0
  Fe  Fe3  1  0.339  0.847  0.339  1.0
  Fe  Fe4  1  0.847  0.339  0.339  1.0
  Fe  Fe5  1  0.660  0.660  0.153  1.0
  Fe  Fe6  1  0.660  0.153  0.660  1.0
  Fe  Fe7  1  0.153  0.660  0.660  1.0
  Fe  Fe8  1  0.710  0.001  0.289  1.0
  Fe  Fe9  1  0.001  0.289  0.710  1.0
  Fe  Fe10  1  0.289  0.710  0.001  1.0
  Fe  Fe11  1  0.001  0.710  0.289  1.0
  Fe  Fe12  1  0.710  0.289  0.001  1.0
  Fe  Fe13  1  0.289  0.001  0.710  1.0
  Fe  Fe14  1  0.001  0.499  0.001  1.0
  Fe  Fe15  1  0.499  0.001  0.001  1.0
  Fe  Fe16  1  0.001  0.001  0.499  1.0
  Fe  Fe17  1  0.911  0.911  0.911  1.0
  Fe  Fe18  1  0.090  0.090  0.090  1.0
[/CIF]
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The material described by TbNdFe17 crystallizes in the trigonal R3m space group. Tb(1) is bonded in a 19-coordinate geometry to one Fe(6), three equivalent Fe(2), three equivalent Fe(4), six equivalent Fe(1), and six equivalent Fe(3) atoms. Nd(1) is bonded in a 19-coordinate geometry to one Fe(5), three equivalent Fe(1), three equivalent Fe(4), six equivalent Fe(2), and six equivalent Fe(3) atoms. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Tb(1), one Nd(1), one Fe(6), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeTb2NdFe9 cuboctahedra that share corners with two equivalent Fe(1)Tb2NdFe9 cuboctahedra, corners with five equivalent Fe(4)TbNdFe10 cuboctahedra, corners with eight equivalent Fe(2)TbNd2Fe9 cuboctahedra,  an edgeedge with one Fe(2)TbNd2Fe9 cuboctahedra, edges with three equivalent Fe(4)TbNdFe10 cuboctahedra, edges with four equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(4)TbNdFe10 cuboctahedra, and faces with four equivalent Fe(1)Tb2NdFe9 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Tb(1), two equivalent Nd(1), one Fe(5), two equivalent Fe(1), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeTbNd2Fe9 cuboctahedra that share corners with two equivalent Fe(2)TbNd2Fe9 cuboctahedra, corners with five equivalent Fe(4)TbNdFe10 cuboctahedra, corners with eight equivalent Fe(1)Tb2NdFe9 cuboctahedra,  an edgeedge with one Fe(1)Tb2NdFe9 cuboctahedra, edges with three equivalent Fe(4)TbNdFe10 cuboctahedra, edges with four equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(4)TbNdFe10 cuboctahedra, and faces with four equivalent Fe(2)TbNd2Fe9 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one Tb(1), one Nd(1), one Fe(5), one Fe(6), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and two equivalent Fe(4) atoms. In the fourth Fe site, Fe(4) is bonded to one Tb(1), one Nd(1), one Fe(5), one Fe(6), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form FeTbNdFe10 cuboctahedra that share corners with four equivalent Fe(4)TbNdFe10 cuboctahedra, corners with five equivalent Fe(1)Tb2NdFe9 cuboctahedra, corners with five equivalent Fe(2)TbNd2Fe9 cuboctahedra, edges with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, edges with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, faces with three equivalent Fe(1)Tb2NdFe9 cuboctahedra, faces with three equivalent Fe(2)TbNd2Fe9 cuboctahedra, and faces with four equivalent Fe(4)TbNdFe10 cuboctahedra. In the fifth Fe site, Fe(5) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(6), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(3) atoms. In the sixth Fe site, Fe(6) is bonded in a 14-coordinate geometry to one Tb(1), one Fe(5), three equivalent Fe(1), three equivalent Fe(4), and six equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_TbNdFe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.377
_cell_length_b   6.377
_cell_length_c   6.377
_cell_angle_alpha   82.556
_cell_angle_beta   82.556
_cell_angle_gamma   82.556
_symmetry_Int_Tables_number   1
_cell_volume   253.243
_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  0.343  0.343  0.343  1.0
  Nd  Nd1  1  0.656  0.656  0.656  1.0
  Fe  Fe2  1  0.339  0.339  0.847  1.0
  Fe  Fe3  1  0.339  0.847  0.339  1.0
  Fe  Fe4  1  0.847  0.339  0.339  1.0
  Fe  Fe5  1  0.660  0.660  0.153  1.0
  Fe  Fe6  1  0.660  0.153  0.660  1.0
  Fe  Fe7  1  0.153  0.660  0.660  1.0
  Fe  Fe8  1  0.710  0.001  0.289  1.0
  Fe  Fe9  1  0.001  0.289  0.710  1.0
  Fe  Fe10  1  0.289  0.710  0.001  1.0
  Fe  Fe11  1  0.001  0.710  0.289  1.0
  Fe  Fe12  1  0.710  0.289  0.001  1.0
  Fe  Fe13  1  0.289  0.001  0.710  1.0
  Fe  Fe14  1  0.001  0.499  0.001  1.0
  Fe  Fe15  1  0.499  0.001  0.001  1.0
  Fe  Fe16  1  0.001  0.001  0.499  1.0
  Fe  Fe17  1  0.911  0.911  0.911  1.0
  Fe  Fe18  1  0.090  0.090  0.090  1.0
[/CIF]
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