The material described by Al3Sn is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Sn(1) atoms to form distorted AlAl8Sn4 cuboctahedra that share corners with twelve equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, and faces with ten equivalent Al(1)Al8Sn4 cuboctahedra. In the second Al site, Al(2) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form AlAl8Sn4 cuboctahedra that share corners with four equivalent Al(2)Al8Sn4 cuboctahedra, corners with eight equivalent Sn(1)Al12 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with six equivalent Sn(1)Al12 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. Sn(1) is bonded to four equivalent Al(2) and eight equivalent Al(1) atoms to form SnAl12 cuboctahedra that share corners with four equivalent Sn(1)Al12 cuboctahedra, corners with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, faces with six equivalent Al(2)Al8Sn4 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. is represented by the CIF file [CIF]
data_Al3Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.178
_cell_length_b   5.178
_cell_length_c   5.178
_cell_angle_alpha   130.611
_cell_angle_beta   130.611
_cell_angle_gamma   72.432
_symmetry_Int_Tables_number   1
_cell_volume   78.213
_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
  Al  Al0  1  0.750  0.250  0.500  1.0
  Al  Al1  1  0.250  0.750  0.500  1.0
  Al  Al2  1  0.500  0.500  0.000  1.0
  Sn  Sn3  1  0.000  0.000  0.000  1.0
[/CIF]
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The material described by Al3Sn is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Sn(1) atoms to form distorted AlAl8Sn4 cuboctahedra that share corners with twelve equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, and faces with ten equivalent Al(1)Al8Sn4 cuboctahedra. In the second Al site, Al(2) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form AlAl8Sn4 cuboctahedra that share corners with four equivalent Al(2)Al8Sn4 cuboctahedra, corners with eight equivalent Sn(1)Al12 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with six equivalent Sn(1)Al12 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. Sn(1) is bonded to four equivalent Al(2) and eight equivalent Al(1) atoms to form SnAl12 cuboctahedra that share corners with four equivalent Sn(1)Al12 cuboctahedra, corners with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, faces with six equivalent Al(2)Al8Sn4 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. is represented by the CIF file [CIF]
data_Al3Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.178
_cell_length_b   5.178
_cell_length_c   5.178
_cell_angle_alpha   130.611
_cell_angle_beta   130.611
_cell_angle_gamma   72.432
_symmetry_Int_Tables_number   1
_cell_volume   78.213
_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
  Al  Al0  1  0.750  0.250  0.500  1.0
  Al  Al1  1  0.250  0.750  0.500  1.0
  Al  Al2  1  0.500  0.500  0.000  1.0
  Sn  Sn3  1  0.000  0.000  0.000  1.0
[/CIF]
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