The compound described by LuFe10Si2 crystallizes in the orthorhombic Fmmm space group. Lu(1) is bonded in a 20-coordinate geometry to four equivalent Fe(1), four equivalent Fe(2), eight equivalent Fe(3), and four equivalent Si(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Lu(1), two equivalent Fe(2), four equivalent Fe(3), five equivalent Fe(1), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded to two equivalent Lu(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Fe(3) atoms to form FeLu2Fe10 cuboctahedra that share corners with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra, corners with six equivalent Fe(2)Lu2Fe10 cuboctahedra, edges with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Lu2Fe10 cuboctahedra, and faces with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Lu(1), two equivalent Fe(2), two equivalent Fe(3), four equivalent Fe(1), and two equivalent Si(1) atoms. Si(1) is bonded to two equivalent Lu(1), four equivalent Fe(1), four equivalent Fe(3), and two equivalent Si(1) atoms to form distorted SiLu2Fe8Si2 cuboctahedra that share corners with four equivalent Fe(2)Lu2Fe10 cuboctahedra, corners with six equivalent Si(1)Lu2Fe8Si2 cuboctahedra, edges with four equivalent Fe(2)Lu2Fe10 cuboctahedra, faces with two equivalent Si(1)Lu2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Lu2Fe10 cuboctahedra. is represented by the CIF file [CIF]
data_Lu(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.221
_cell_length_b   6.318
_cell_length_c   6.249
_cell_angle_alpha   81.715
_cell_angle_beta   49.503
_cell_angle_gamma   48.781
_symmetry_Int_Tables_number   1
_cell_volume   161.211
_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
  Lu  Lu0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.003  0.642  0.358  1.0
  Fe  Fe2  1  0.997  0.358  0.642  1.0
  Fe  Fe3  1  0.642  0.003  0.997  1.0
  Fe  Fe4  1  0.358  0.997  0.003  1.0
  Fe  Fe5  1  0.500  0.000  0.500  1.0
  Fe  Fe6  1  0.000  0.500  0.000  1.0
  Fe  Fe7  1  0.499  0.719  0.281  1.0
  Fe  Fe8  1  0.501  0.281  0.719  1.0
  Fe  Fe9  1  0.719  0.499  0.501  1.0
  Fe  Fe10  1  0.281  0.501  0.499  1.0
  Si  Si11  1  0.000  0.000  0.500  1.0
  Si  Si12  1  0.500  0.500  0.000  1.0
[/CIF]
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The compound described by LuFe10Si2 crystallizes in the orthorhombic Fmmm space group. Lu(1) is bonded in a 20-coordinate geometry to four equivalent Fe(1), four equivalent Fe(2), eight equivalent Fe(3), and four equivalent Si(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Lu(1), two equivalent Fe(2), four equivalent Fe(3), five equivalent Fe(1), and two equivalent Si(1) atoms. In the second Fe site, Fe(2) is bonded to two equivalent Lu(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Fe(3) atoms to form FeLu2Fe10 cuboctahedra that share corners with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra, corners with six equivalent Fe(2)Lu2Fe10 cuboctahedra, edges with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra, faces with two equivalent Fe(2)Lu2Fe10 cuboctahedra, and faces with four equivalent Si(1)Lu2Fe8Si2 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Lu(1), two equivalent Fe(2), two equivalent Fe(3), four equivalent Fe(1), and two equivalent Si(1) atoms. Si(1) is bonded to two equivalent Lu(1), four equivalent Fe(1), four equivalent Fe(3), and two equivalent Si(1) atoms to form distorted SiLu2Fe8Si2 cuboctahedra that share corners with four equivalent Fe(2)Lu2Fe10 cuboctahedra, corners with six equivalent Si(1)Lu2Fe8Si2 cuboctahedra, edges with four equivalent Fe(2)Lu2Fe10 cuboctahedra, faces with two equivalent Si(1)Lu2Fe8Si2 cuboctahedra, and faces with four equivalent Fe(2)Lu2Fe10 cuboctahedra. is represented by the CIF file [CIF]
data_Lu(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.221
_cell_length_b   6.318
_cell_length_c   6.249
_cell_angle_alpha   81.715
_cell_angle_beta   49.503
_cell_angle_gamma   48.781
_symmetry_Int_Tables_number   1
_cell_volume   161.211
_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
  Lu  Lu0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.003  0.642  0.358  1.0
  Fe  Fe2  1  0.997  0.358  0.642  1.0
  Fe  Fe3  1  0.642  0.003  0.997  1.0
  Fe  Fe4  1  0.358  0.997  0.003  1.0
  Fe  Fe5  1  0.500  0.000  0.500  1.0
  Fe  Fe6  1  0.000  0.500  0.000  1.0
  Fe  Fe7  1  0.499  0.719  0.281  1.0
  Fe  Fe8  1  0.501  0.281  0.719  1.0
  Fe  Fe9  1  0.719  0.499  0.501  1.0
  Fe  Fe10  1  0.281  0.501  0.499  1.0
  Si  Si11  1  0.000  0.000  0.500  1.0
  Si  Si12  1  0.500  0.500  0.000  1.0
[/CIF]
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