data_YSi2Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.01
_cell_length_b   5.01
_cell_length_c   5.01
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   YSi2Sb
_chemical_formula_sum   'Y1 Si2 Sb1'
_cell_volume   88.91
_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  Y3  1  0.0  0.0  0.0  1.0
  Si  Si1  1  0.77  0.77  0.77  1.0
  Si  Si2  1  0.31  0.31  0.31  1.0
  Sb  Sb0  1  0.54  0.54  0.54  1.0

data_YSi2Sb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.01
_cell_length_b   5.01
_cell_length_c   12.27
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   YSi2Sb
_chemical_formula_sum   'Y3 Si6 Sb3'
_cell_volume   266.74
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  3  0.0  0.0  0.0  1.0
  Si  Si1  3  0.0  0.0  0.23  1.0
  Si  Si2  3  0.0  0.0  0.69  1.0
  Sb  Sb3  3  0.0  0.0  0.46  1.0

Y Si Si Sb
YSi2Sb is Heusler structured and crystallizes in the trigonal R3m space group. Y(1) is bonded in a 10-coordinate geometry to three equivalent Si(2), four equivalent Si(1), and three equivalent Sb(1) atoms. All Y(1)-Si(2) bond lengths are 2.90 Å. There is one shorter (2.81 Å) and three longer (3.16 Å) Y(1)-Si(1) bond lengths. All Y(1)-Sb(1) bond lengths are 3.27 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Y(1) and four equivalent Sb(1) atoms. There is one shorter (2.81 Å) and three longer (3.16 Å) Si(1)-Sb(1) bond lengths. In the second Si site, Si(2) is bonded to three equivalent Y(1) and four equivalent Sb(1) atoms to form a mixture of distorted corner and edge-sharing SiY3Sb4 trigonal pyramids. There is one shorter (2.81 Å) and three longer (3.16 Å) Si(2)-Sb(1) bond lengths. Sb(1) is bonded in a 11-coordinate geometry to three equivalent Y(1), four equivalent Si(1), and four equivalent Si(2) atoms.