The compound described by Nd2Fe17 crystallizes in the trigonal R-3m space group. Nd(1) is bonded in a 19-coordinate geometry to one Fe(4), three equivalent Fe(1), six equivalent Fe(2), and nine equivalent Fe(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Nd(1), two equivalent Fe(4), four equivalent Fe(2), and four equivalent Fe(3) atoms to form FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(3)Nd3Fe9 cuboctahedra, edges with four equivalent Fe(2)Nd2Fe10 cuboctahedra, edges with six equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with four equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with six equivalent Fe(3)Nd3Fe9 cuboctahedra, and faces with eight equivalent Fe(2)Nd2Fe10 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form distorted FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Nd3Fe9 cuboctahedra, corners with twelve equivalent Fe(2)Nd2Fe10 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe10 cuboctahedra, edges with two equivalent Fe(1)Nd2Fe10 cuboctahedra, edges with two equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with four equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with seven equivalent Fe(2)Nd2Fe10 cuboctahedra, and faces with ten equivalent Fe(3)Nd3Fe9 cuboctahedra. In the third Fe site, Fe(3) is bonded to three equivalent Nd(1), one Fe(4), two equivalent Fe(1), two equivalent Fe(3), and four equivalent Fe(2) atoms to form FeNd3Fe9 cuboctahedra that share corners with five equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(3)Nd3Fe9 cuboctahedra, edges with two equivalent Fe(2)Nd2Fe10 cuboctahedra, edges with three equivalent Fe(1)Nd2Fe10 cuboctahedra, edges with five equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with three equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with seven equivalent Fe(3)Nd3Fe9 cuboctahedra, and faces with ten equivalent Fe(2)Nd2Fe10 cuboctahedra. In the fourth Fe site, Fe(4) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(4), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nd2Fe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.468
_cell_length_b   6.468
_cell_length_c   6.468
_cell_angle_alpha   83.134
_cell_angle_beta   83.134
_cell_angle_gamma   83.134
_symmetry_Int_Tables_number   1
_cell_volume   265.193
_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
  Nd  Nd0  1  0.658  0.658  0.658  1.0
  Nd  Nd1  1  0.342  0.342  0.342  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.500  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.711  0.289  0.000  1.0
  Fe  Fe6  1  0.000  0.711  0.289  1.0
  Fe  Fe7  1  0.289  0.000  0.711  1.0
  Fe  Fe8  1  0.000  0.289  0.711  1.0
  Fe  Fe9  1  0.711  0.000  0.289  1.0
  Fe  Fe10  1  0.289  0.711  0.000  1.0
  Fe  Fe11  1  0.341  0.341  0.846  1.0
  Fe  Fe12  1  0.846  0.341  0.341  1.0
  Fe  Fe13  1  0.341  0.846  0.341  1.0
  Fe  Fe14  1  0.659  0.659  0.154  1.0
  Fe  Fe15  1  0.154  0.659  0.659  1.0
  Fe  Fe16  1  0.659  0.154  0.659  1.0
  Fe  Fe17  1  0.903  0.903  0.903  1.0
  Fe  Fe18  1  0.097  0.097  0.097  1.0
[/CIF]
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The compound described by Nd2Fe17 crystallizes in the trigonal R-3m space group. Nd(1) is bonded in a 19-coordinate geometry to one Fe(4), three equivalent Fe(1), six equivalent Fe(2), and nine equivalent Fe(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Nd(1), two equivalent Fe(4), four equivalent Fe(2), and four equivalent Fe(3) atoms to form FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(3)Nd3Fe9 cuboctahedra, edges with four equivalent Fe(2)Nd2Fe10 cuboctahedra, edges with six equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with four equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with six equivalent Fe(3)Nd3Fe9 cuboctahedra, and faces with eight equivalent Fe(2)Nd2Fe10 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form distorted FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Nd3Fe9 cuboctahedra, corners with twelve equivalent Fe(2)Nd2Fe10 cuboctahedra,  an edgeedge with one Fe(2)Nd2Fe10 cuboctahedra, edges with two equivalent Fe(1)Nd2Fe10 cuboctahedra, edges with two equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with four equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with seven equivalent Fe(2)Nd2Fe10 cuboctahedra, and faces with ten equivalent Fe(3)Nd3Fe9 cuboctahedra. In the third Fe site, Fe(3) is bonded to three equivalent Nd(1), one Fe(4), two equivalent Fe(1), two equivalent Fe(3), and four equivalent Fe(2) atoms to form FeNd3Fe9 cuboctahedra that share corners with five equivalent Fe(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(2)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(3)Nd3Fe9 cuboctahedra, edges with two equivalent Fe(2)Nd2Fe10 cuboctahedra, edges with three equivalent Fe(1)Nd2Fe10 cuboctahedra, edges with five equivalent Fe(3)Nd3Fe9 cuboctahedra, faces with three equivalent Fe(1)Nd2Fe10 cuboctahedra, faces with seven equivalent Fe(3)Nd3Fe9 cuboctahedra, and faces with ten equivalent Fe(2)Nd2Fe10 cuboctahedra. In the fourth Fe site, Fe(4) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(4), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nd2Fe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.468
_cell_length_b   6.468
_cell_length_c   6.468
_cell_angle_alpha   83.134
_cell_angle_beta   83.134
_cell_angle_gamma   83.134
_symmetry_Int_Tables_number   1
_cell_volume   265.193
_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
  Nd  Nd0  1  0.658  0.658  0.658  1.0
  Nd  Nd1  1  0.342  0.342  0.342  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.500  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.711  0.289  0.000  1.0
  Fe  Fe6  1  0.000  0.711  0.289  1.0
  Fe  Fe7  1  0.289  0.000  0.711  1.0
  Fe  Fe8  1  0.000  0.289  0.711  1.0
  Fe  Fe9  1  0.711  0.000  0.289  1.0
  Fe  Fe10  1  0.289  0.711  0.000  1.0
  Fe  Fe11  1  0.341  0.341  0.846  1.0
  Fe  Fe12  1  0.846  0.341  0.341  1.0
  Fe  Fe13  1  0.341  0.846  0.341  1.0
  Fe  Fe14  1  0.659  0.659  0.154  1.0
  Fe  Fe15  1  0.154  0.659  0.659  1.0
  Fe  Fe16  1  0.659  0.154  0.659  1.0
  Fe  Fe17  1  0.903  0.903  0.903  1.0
  Fe  Fe18  1  0.097  0.097  0.097  1.0
[/CIF]
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