data_Y(AlSn)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.46
_cell_length_b   6.46
_cell_length_c   6.46
_cell_angle_alpha   136.58
_cell_angle_beta   136.58
_cell_angle_gamma   63.09
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Y(AlSn)2
_chemical_formula_sum   'Y1 Al2 Sn2'
_cell_volume   126.02
_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  Y4  1  0.0  0.0  0.0  1.0
  Al  Al0  1  0.0  0.0  0.75  1.0
  Al  Al1  1  0.0  0.0  0.27  1.0
  Sn  Sn2  1  0.0  0.39  0.75  1.0
  Sn  Sn3  1  0.39  0.0  0.75  1.0

data_Y(AlSn)2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.76
_cell_length_b   6.76
_cell_length_c   6.46
_cell_angle_alpha   90.0
_cell_angle_beta   121.55
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Y(AlSn)2
_chemical_formula_sum   'Y2 Al4 Sn4'
_cell_volume   252.03
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.0  1.0
  Al  Al1  2  0.0  0.0  0.27  1.0
  Al  Al2  2  0.0  0.0  0.75  1.0
  Sn  Sn3  4  0.3  0.3  0.36  1.0

Y Al Al Sn Sn
Y Al Al Sn Sn 0 1 o o - 0 2 o o o 1 3 o o o 1 4 o o o 2 3 o o o 2 3 o - - 2 4 o o o 2 4 - o - 3 4 o o o 
Y(AlSn)2 crystallizes in the monoclinic Cm space group. Y(1) is bonded in a distorted linear geometry to one Al(1), one Al(2), and two equivalent Sn(1) atoms. The Y(1)-Al(1) bond length is 1.64 Å. The Y(1)-Al(2) bond length is 1.76 Å. Both Y(1)-Sn(1) bond lengths are 2.99 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 3-coordinate geometry to one Y(1) and two equivalent Sn(1) atoms. Both Al(1)-Sn(1) bond lengths are 2.49 Å. In the second Al site, Al(2) is bonded in a 5-coordinate geometry to one Y(1) and four equivalent Sn(1) atoms. There are two shorter (2.16 Å) and two longer (2.75 Å) Al(2)-Sn(1) bond lengths. Sn(1) is bonded in a 4-coordinate geometry to one Y(1), one Al(1), and two equivalent Al(2) atoms.