data_SrSiAu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.84
_cell_length_b   4.84
_cell_length_c   4.84
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrSiAu
_chemical_formula_sum   'Sr1 Si1 Au1'
_cell_volume   80.05
_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
  Sr  Sr2  1  0.42  0.42  0.42  1.0
  Si  Si1  1  0.0  0.0  0.0  1.0
  Au  Au0  1  0.71  0.71  0.71  1.0

data_SrSiAu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.84
_cell_length_b   4.84
_cell_length_c   11.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SrSiAu
_chemical_formula_sum   'Sr3 Si3 Au3'
_cell_volume   240.16
_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
  Sr  Sr0  3  0.0  0.0  0.58  1.0
  Si  Si1  3  0.0  0.0  -0.0  1.0
  Au  Au2  3  0.0  0.0  0.29  1.0

Sr Si Au
Sr Si Au 0 1 o o + 0 1 o + o 0 1 + o o 0 2 - o o 0 2 o - o 0 2 o o - 1 2 - - o 1 2 - o - 1 2 o - - 
SrAuSi is half-Heusler structured and crystallizes in the trigonal R3m space group. Sr(1) is bonded to four equivalent Au(1) and three equivalent Si(1) atoms to form distorted SrSi3Au4 hexagonal pyramids that share corners with three equivalent Au(1)Sr4Si3 hexagonal pyramids, corners with six equivalent Sr(1)Si3Au4 hexagonal pyramids, edges with three equivalent Au(1)Sr4Si3 hexagonal pyramids, and edges with six equivalent Sr(1)Si3Au4 hexagonal pyramids. There are three shorter (2.84 Å) and one longer (3.43 Å) Sr(1)-Au(1) bond length. All Sr(1)-Si(1) bond lengths are 2.98 Å. Au(1) is bonded to four equivalent Sr(1) and three equivalent Si(1) atoms to form distorted AuSr4Si3 hexagonal pyramids that share corners with three equivalent Sr(1)Si3Au4 hexagonal pyramids, corners with six equivalent Au(1)Sr4Si3 hexagonal pyramids, edges with three equivalent Sr(1)Si3Au4 hexagonal pyramids, and edges with six equivalent Au(1)Sr4Si3 hexagonal pyramids. All Au(1)-Si(1) bond lengths are 2.84 Å. Si(1) is bonded in a distorted hexagonal planar geometry to three equivalent Sr(1) and three equivalent Au(1) atoms.