The crystal structure described by YFe10Si2 crystallizes in the orthorhombic Immm space group. Y(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 Y(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 Y(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 Y(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 Y(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 FeY2Fe8Si2 cuboctahedra that share corners with four equivalent Si(1)Y2Fe10 cuboctahedra, corners with ten equivalent Fe(4)Y2Fe8Si2 cuboctahedra, edges with two equivalent Si(1)Y2Fe10 cuboctahedra, edges with four equivalent Fe(4)Y2Fe8Si2 cuboctahedra, faces with four equivalent Si(1)Y2Fe10 cuboctahedra, and faces with six equivalent Fe(4)Y2Fe8Si2 cuboctahedra. Si(1) is bonded to two equivalent Y(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(4) atoms to form distorted SiY2Fe10 cuboctahedra that share corners with six equivalent Si(1)Y2Fe10 cuboctahedra, corners with eight equivalent Fe(4)Y2Fe8Si2 cuboctahedra, edges with three equivalent Si(1)Y2Fe10 cuboctahedra, edges with four equivalent Fe(4)Y2Fe8Si2 cuboctahedra,  a faceface with one Si(1)Y2Fe10 cuboctahedra, and faces with eight equivalent Fe(4)Y2Fe8Si2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.752
_cell_length_b   6.352
_cell_length_c   6.352
_cell_angle_alpha   98.384
_cell_angle_beta   111.964
_cell_angle_gamma   68.036
_symmetry_Int_Tables_number   1
_cell_volume   164.887
_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
  Y  Y0  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  0.355  0.355  1.0
  Fe  Fe4  1  0.000  0.645  0.645  1.0
  Fe  Fe5  1  0.500  0.790  0.790  1.0
  Fe  Fe6  1  0.500  0.210  0.210  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  0.736  0.764  0.236  1.0
  Si  Si12  1  0.264  0.236  0.764  1.0
[/CIF]
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The crystal structure described by YFe10Si2 crystallizes in the orthorhombic Immm space group. Y(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 Y(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 Y(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 Y(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 Y(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 FeY2Fe8Si2 cuboctahedra that share corners with four equivalent Si(1)Y2Fe10 cuboctahedra, corners with ten equivalent Fe(4)Y2Fe8Si2 cuboctahedra, edges with two equivalent Si(1)Y2Fe10 cuboctahedra, edges with four equivalent Fe(4)Y2Fe8Si2 cuboctahedra, faces with four equivalent Si(1)Y2Fe10 cuboctahedra, and faces with six equivalent Fe(4)Y2Fe8Si2 cuboctahedra. Si(1) is bonded to two equivalent Y(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(4) atoms to form distorted SiY2Fe10 cuboctahedra that share corners with six equivalent Si(1)Y2Fe10 cuboctahedra, corners with eight equivalent Fe(4)Y2Fe8Si2 cuboctahedra, edges with three equivalent Si(1)Y2Fe10 cuboctahedra, edges with four equivalent Fe(4)Y2Fe8Si2 cuboctahedra,  a faceface with one Si(1)Y2Fe10 cuboctahedra, and faces with eight equivalent Fe(4)Y2Fe8Si2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y(Fe5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.752
_cell_length_b   6.352
_cell_length_c   6.352
_cell_angle_alpha   98.384
_cell_angle_beta   111.964
_cell_angle_gamma   68.036
_symmetry_Int_Tables_number   1
_cell_volume   164.887
_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
  Y  Y0  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  0.355  0.355  1.0
  Fe  Fe4  1  0.000  0.645  0.645  1.0
  Fe  Fe5  1  0.500  0.790  0.790  1.0
  Fe  Fe6  1  0.500  0.210  0.210  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  0.736  0.764  0.236  1.0
  Si  Si12  1  0.264  0.236  0.764  1.0
[/CIF]
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