The structure described by Fe3Sn crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to eight Fe(1,1) and four equivalent Sn(1) atoms to form distorted FeFe8Sn4 cuboctahedra that share corners with four equivalent Sn(1)Fe12 cuboctahedra; corners with fourteen Fe(1,1)Fe8Sn4 cuboctahedra; edges with six equivalent Sn(1)Fe12 cuboctahedra; edges with twelve Fe(1,1)Fe8Sn4 cuboctahedra; faces with four equivalent Sn(1)Fe12 cuboctahedra; and faces with sixteen Fe(1,1)Fe8Sn4 cuboctahedra. In the second Fe site, Fe(1) is bonded to eight equivalent Fe(1) and four equivalent Sn(1) atoms to form distorted FeFe8Sn4 cuboctahedra that share corners with four equivalent Sn(1)Fe12 cuboctahedra; corners with fourteen Fe(1,1)Fe8Sn4 cuboctahedra; edges with six equivalent Sn(1)Fe12 cuboctahedra; edges with twelve equivalent Fe(1)Fe8Sn4 cuboctahedra; faces with four equivalent Sn(1)Fe12 cuboctahedra; and faces with sixteen Fe(1,1)Fe8Sn4 cuboctahedra. Sn(1) is bonded to twelve Fe(1,1) atoms to form SnFe12 cuboctahedra that share corners with six equivalent Sn(1)Fe12 cuboctahedra; corners with twelve Fe(1,1)Fe8Sn4 cuboctahedra; edges with eighteen Fe(1,1)Fe8Sn4 cuboctahedra; faces with eight equivalent Sn(1)Fe12 cuboctahedra; and faces with twelve Fe(1,1)Fe8Sn4 cuboctahedra. is represented by the CIF file [CIF]
data_Fe3Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.310
_cell_length_b   5.487
_cell_length_c   5.487
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   112.371
_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
  Fe  Fe0  1  0.750  0.849  0.151  1.0
  Fe  Fe1  1  0.750  0.302  0.151  1.0
  Fe  Fe2  1  0.750  0.849  0.698  1.0
  Fe  Fe3  1  0.250  0.151  0.849  1.0
  Fe  Fe4  1  0.250  0.698  0.849  1.0
  Fe  Fe5  1  0.250  0.151  0.302  1.0
  Sn  Sn6  1  0.750  0.333  0.667  1.0
  Sn  Sn7  1  0.250  0.667  0.333  1.0
[/CIF]
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The structure described by Fe3Sn crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to eight Fe(1,1) and four equivalent Sn(1) atoms to form distorted FeFe8Sn4 cuboctahedra that share corners with four equivalent Sn(1)Fe12 cuboctahedra; corners with fourteen Fe(1,1)Fe8Sn4 cuboctahedra; edges with six equivalent Sn(1)Fe12 cuboctahedra; edges with twelve Fe(1,1)Fe8Sn4 cuboctahedra; faces with four equivalent Sn(1)Fe12 cuboctahedra; and faces with sixteen Fe(1,1)Fe8Sn4 cuboctahedra. In the second Fe site, Fe(1) is bonded to eight equivalent Fe(1) and four equivalent Sn(1) atoms to form distorted FeFe8Sn4 cuboctahedra that share corners with four equivalent Sn(1)Fe12 cuboctahedra; corners with fourteen Fe(1,1)Fe8Sn4 cuboctahedra; edges with six equivalent Sn(1)Fe12 cuboctahedra; edges with twelve equivalent Fe(1)Fe8Sn4 cuboctahedra; faces with four equivalent Sn(1)Fe12 cuboctahedra; and faces with sixteen Fe(1,1)Fe8Sn4 cuboctahedra. Sn(1) is bonded to twelve Fe(1,1) atoms to form SnFe12 cuboctahedra that share corners with six equivalent Sn(1)Fe12 cuboctahedra; corners with twelve Fe(1,1)Fe8Sn4 cuboctahedra; edges with eighteen Fe(1,1)Fe8Sn4 cuboctahedra; faces with eight equivalent Sn(1)Fe12 cuboctahedra; and faces with twelve Fe(1,1)Fe8Sn4 cuboctahedra. is represented by the CIF file [CIF]
data_Fe3Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.310
_cell_length_b   5.487
_cell_length_c   5.487
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   112.371
_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
  Fe  Fe0  1  0.750  0.849  0.151  1.0
  Fe  Fe1  1  0.750  0.302  0.151  1.0
  Fe  Fe2  1  0.750  0.849  0.698  1.0
  Fe  Fe3  1  0.250  0.151  0.849  1.0
  Fe  Fe4  1  0.250  0.698  0.849  1.0
  Fe  Fe5  1  0.250  0.151  0.302  1.0
  Sn  Sn6  1  0.750  0.333  0.667  1.0
  Sn  Sn7  1  0.250  0.667  0.333  1.0
[/CIF]
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