The material described by NdFe10Si2 crystallizes in the orthorhombic Immm space group. Nd(1) is bonded in a 20-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(3), eight equivalent Fe(4), and four equivalent Si(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(1), two equivalent Fe(3), four equivalent Fe(2), four equivalent Fe(4), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(2), two equivalent Fe(3), four equivalent Fe(1), four equivalent Fe(4), and two equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(4), and two equivalent Si(1) atoms. In the fourth Fe site, Fe(4) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Si(1) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with four equivalent Si(1)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Si(1)Nd2Fe10 cuboctahedra, edges with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with four equivalent Si(1)Nd2Fe10 cuboctahedra, and faces with six equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. Si(1) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(4) atoms to form SiNd2Fe10 cuboctahedra that share corners with six equivalent Si(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, edges with three equivalent Si(1)Nd2Fe10 cuboctahedra, edges with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Si(1)Nd2Fe10 cuboctahedra, and faces with eight equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. is represented by the CIF file [CIF]
data_Nd(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.728
_cell_length_b   6.405
_cell_length_c   6.405
_cell_angle_alpha   98.216
_cell_angle_beta   111.658
_cell_angle_gamma   68.342
_symmetry_Int_Tables_number   1
_cell_volume   167.548
_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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.638  0.362  0.638  1.0
  Fe  Fe2  1  0.362  0.638  0.362  1.0
  Fe  Fe3  1  0.000  0.356  0.356  1.0
  Fe  Fe4  1  0.000  0.644  0.644  1.0
  Fe  Fe5  1  0.500  0.784  0.784  1.0
  Fe  Fe6  1  0.500  0.216  0.216  1.0
  Fe  Fe7  1  0.500  0.000  0.500  1.0
  Fe  Fe8  1  0.000  0.000  0.500  1.0
  Fe  Fe9  1  0.500  0.500  0.000  1.0
  Fe  Fe10  1  0.000  0.500  0.000  1.0
  Si  Si11  1  0.742  0.758  0.242  1.0
  Si  Si12  1  0.258  0.242  0.758  1.0
[/CIF]
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The material described by NdFe10Si2 crystallizes in the orthorhombic Immm space group. Nd(1) is bonded in a 20-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(3), eight equivalent Fe(4), and four equivalent Si(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(1), two equivalent Fe(3), four equivalent Fe(2), four equivalent Fe(4), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded in a 14-coordinate geometry to one Nd(1), one Fe(2), two equivalent Fe(3), four equivalent Fe(1), four equivalent Fe(4), and two equivalent Si(1) atoms. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(4), and two equivalent Si(1) atoms. In the fourth Fe site, Fe(4) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Si(1) atoms to form distorted FeNd2Fe8Si2 cuboctahedra that share corners with four equivalent Si(1)Nd2Fe10 cuboctahedra, corners with ten equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, edges with two equivalent Si(1)Nd2Fe10 cuboctahedra, edges with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, faces with four equivalent Si(1)Nd2Fe10 cuboctahedra, and faces with six equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. Si(1) is bonded to two equivalent Nd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(4) atoms to form SiNd2Fe10 cuboctahedra that share corners with six equivalent Si(1)Nd2Fe10 cuboctahedra, corners with eight equivalent Fe(4)Nd2Fe8Si2 cuboctahedra, edges with three equivalent Si(1)Nd2Fe10 cuboctahedra, edges with four equivalent Fe(4)Nd2Fe8Si2 cuboctahedra,  a faceface with one Si(1)Nd2Fe10 cuboctahedra, and faces with eight equivalent Fe(4)Nd2Fe8Si2 cuboctahedra. is represented by the CIF file [CIF]
data_Nd(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.728
_cell_length_b   6.405
_cell_length_c   6.405
_cell_angle_alpha   98.216
_cell_angle_beta   111.658
_cell_angle_gamma   68.342
_symmetry_Int_Tables_number   1
_cell_volume   167.548
_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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.638  0.362  0.638  1.0
  Fe  Fe2  1  0.362  0.638  0.362  1.0
  Fe  Fe3  1  0.000  0.356  0.356  1.0
  Fe  Fe4  1  0.000  0.644  0.644  1.0
  Fe  Fe5  1  0.500  0.784  0.784  1.0
  Fe  Fe6  1  0.500  0.216  0.216  1.0
  Fe  Fe7  1  0.500  0.000  0.500  1.0
  Fe  Fe8  1  0.000  0.000  0.500  1.0
  Fe  Fe9  1  0.500  0.500  0.000  1.0
  Fe  Fe10  1  0.000  0.500  0.000  1.0
  Si  Si11  1  0.742  0.758  0.242  1.0
  Si  Si12  1  0.258  0.242  0.758  1.0
[/CIF]
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