The material described by ErNdFe17 crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded in a 18-coordinate geometry to six equivalent Fe(1) and twelve equivalent Fe(2) atoms. Nd(1) is bonded in a 20-coordinate geometry to two equivalent Fe(3), six equivalent Fe(1), six equivalent Fe(2), and six equivalent Fe(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded to two equivalent Nd(1), two equivalent Fe(3), four equivalent Fe(1), and four equivalent Fe(2) atoms to form FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(4)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(2)NdEr2Fe9 cuboctahedra, edges with six equivalent Fe(2)NdEr2Fe9 cuboctahedra, faces with four equivalent Fe(2)NdEr2Fe9 cuboctahedra, and faces with six equivalent Fe(4)Nd2Fe10 cuboctahedra. In the second Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Er(1), one Nd(1), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), and four equivalent Fe(2) atoms. In the third Fe site, Fe(2) is bonded to two equivalent Er(1), one Nd(1), one Fe(3), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(1) atoms to form distorted FeNdEr2Fe9 cuboctahedra that share corners with five equivalent Fe(4)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(2)NdEr2Fe9 cuboctahedra, edges with three equivalent Fe(4)Nd2Fe10 cuboctahedra, edges with five equivalent Fe(2)NdEr2Fe9 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe10 cuboctahedra, and faces with eight equivalent Fe(2)NdEr2Fe9 cuboctahedra. In the fourth Fe site, Fe(3) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(3), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_NdErFe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.522
_cell_length_b   8.522
_cell_length_c   8.273
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   520.347
_cell_formula_units_Z   2
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  0.333  0.667  0.750  1.0
  Nd  Nd1  1  0.667  0.333  0.250  1.0
  Er  Er2  1  0.000  0.000  0.250  1.0
  Er  Er3  1  0.000  0.000  0.750  1.0
  Fe  Fe4  1  0.328  0.369  0.250  1.0
  Fe  Fe5  1  0.631  0.958  0.250  1.0
  Fe  Fe6  1  0.042  0.672  0.250  1.0
  Fe  Fe7  1  0.631  0.672  0.250  1.0
  Fe  Fe8  1  0.042  0.369  0.250  1.0
  Fe  Fe9  1  0.328  0.958  0.250  1.0
  Fe  Fe10  1  0.672  0.631  0.750  1.0
  Fe  Fe11  1  0.369  0.042  0.750  1.0
  Fe  Fe12  1  0.958  0.328  0.750  1.0
  Fe  Fe13  1  0.369  0.328  0.750  1.0
  Fe  Fe14  1  0.958  0.631  0.750  1.0
  Fe  Fe15  1  0.672  0.042  0.750  1.0
  Fe  Fe16  1  0.165  0.835  0.515  1.0
  Fe  Fe17  1  0.165  0.330  0.515  1.0
  Fe  Fe18  1  0.670  0.835  0.515  1.0
  Fe  Fe19  1  0.835  0.165  0.485  1.0
  Fe  Fe20  1  0.835  0.670  0.485  1.0
  Fe  Fe21  1  0.330  0.165  0.485  1.0
  Fe  Fe22  1  0.835  0.165  0.015  1.0
  Fe  Fe23  1  0.835  0.670  0.015  1.0
  Fe  Fe24  1  0.330  0.165  0.015  1.0
  Fe  Fe25  1  0.165  0.835  0.985  1.0
  Fe  Fe26  1  0.165  0.330  0.985  1.0
  Fe  Fe27  1  0.670  0.835  0.985  1.0
  Fe  Fe28  1  0.333  0.667  0.393  1.0
  Fe  Fe29  1  0.667  0.333  0.607  1.0
  Fe  Fe30  1  0.667  0.333  0.893  1.0
  Fe  Fe31  1  0.333  0.667  0.107  1.0
  Fe  Fe32  1  0.500  0.500  0.500  1.0
  Fe  Fe33  1  0.500  0.000  0.500  1.0
  Fe  Fe34  1  0.000  0.500  0.500  1.0
  Fe  Fe35  1  0.500  0.500  0.000  1.0
  Fe  Fe36  1  0.500  0.000  0.000  1.0
  Fe  Fe37  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by ErNdFe17 crystallizes in the hexagonal P6_3/mmc space group. Er(1) is bonded in a 18-coordinate geometry to six equivalent Fe(1) and twelve equivalent Fe(2) atoms. Nd(1) is bonded in a 20-coordinate geometry to two equivalent Fe(3), six equivalent Fe(1), six equivalent Fe(2), and six equivalent Fe(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded to two equivalent Nd(1), two equivalent Fe(3), four equivalent Fe(1), and four equivalent Fe(2) atoms to form FeNd2Fe10 cuboctahedra that share corners with four equivalent Fe(4)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(2)NdEr2Fe9 cuboctahedra, edges with six equivalent Fe(2)NdEr2Fe9 cuboctahedra, faces with four equivalent Fe(2)NdEr2Fe9 cuboctahedra, and faces with six equivalent Fe(4)Nd2Fe10 cuboctahedra. In the second Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Er(1), one Nd(1), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), and four equivalent Fe(2) atoms. In the third Fe site, Fe(2) is bonded to two equivalent Er(1), one Nd(1), one Fe(3), two equivalent Fe(2), two equivalent Fe(4), and four equivalent Fe(1) atoms to form distorted FeNdEr2Fe9 cuboctahedra that share corners with five equivalent Fe(4)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(2)NdEr2Fe9 cuboctahedra, edges with three equivalent Fe(4)Nd2Fe10 cuboctahedra, edges with five equivalent Fe(2)NdEr2Fe9 cuboctahedra, faces with two equivalent Fe(4)Nd2Fe10 cuboctahedra, and faces with eight equivalent Fe(2)NdEr2Fe9 cuboctahedra. In the fourth Fe site, Fe(3) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(3), three equivalent Fe(2), three equivalent Fe(4), and six equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_NdErFe17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.522
_cell_length_b   8.522
_cell_length_c   8.273
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   520.347
_cell_formula_units_Z   2
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  0.333  0.667  0.750  1.0
  Nd  Nd1  1  0.667  0.333  0.250  1.0
  Er  Er2  1  0.000  0.000  0.250  1.0
  Er  Er3  1  0.000  0.000  0.750  1.0
  Fe  Fe4  1  0.328  0.369  0.250  1.0
  Fe  Fe5  1  0.631  0.958  0.250  1.0
  Fe  Fe6  1  0.042  0.672  0.250  1.0
  Fe  Fe7  1  0.631  0.672  0.250  1.0
  Fe  Fe8  1  0.042  0.369  0.250  1.0
  Fe  Fe9  1  0.328  0.958  0.250  1.0
  Fe  Fe10  1  0.672  0.631  0.750  1.0
  Fe  Fe11  1  0.369  0.042  0.750  1.0
  Fe  Fe12  1  0.958  0.328  0.750  1.0
  Fe  Fe13  1  0.369  0.328  0.750  1.0
  Fe  Fe14  1  0.958  0.631  0.750  1.0
  Fe  Fe15  1  0.672  0.042  0.750  1.0
  Fe  Fe16  1  0.165  0.835  0.515  1.0
  Fe  Fe17  1  0.165  0.330  0.515  1.0
  Fe  Fe18  1  0.670  0.835  0.515  1.0
  Fe  Fe19  1  0.835  0.165  0.485  1.0
  Fe  Fe20  1  0.835  0.670  0.485  1.0
  Fe  Fe21  1  0.330  0.165  0.485  1.0
  Fe  Fe22  1  0.835  0.165  0.015  1.0
  Fe  Fe23  1  0.835  0.670  0.015  1.0
  Fe  Fe24  1  0.330  0.165  0.015  1.0
  Fe  Fe25  1  0.165  0.835  0.985  1.0
  Fe  Fe26  1  0.165  0.330  0.985  1.0
  Fe  Fe27  1  0.670  0.835  0.985  1.0
  Fe  Fe28  1  0.333  0.667  0.393  1.0
  Fe  Fe29  1  0.667  0.333  0.607  1.0
  Fe  Fe30  1  0.667  0.333  0.893  1.0
  Fe  Fe31  1  0.333  0.667  0.107  1.0
  Fe  Fe32  1  0.500  0.500  0.500  1.0
  Fe  Fe33  1  0.500  0.000  0.500  1.0
  Fe  Fe34  1  0.000  0.500  0.500  1.0
  Fe  Fe35  1  0.500  0.500  0.000  1.0
  Fe  Fe36  1  0.500  0.000  0.000  1.0
  Fe  Fe37  1  0.000  0.500  0.000  1.0
[/CIF]
.