data_Sr2PtAu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   5.19
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr2PtAu
_chemical_formula_sum   'Sr2 Pt1 Au1'
_cell_volume   98.62
_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  0.83  0.83  0.83  1.0
  Sr  Sr3  1  0.0  0.0  0.0  1.0
  Pt  Pt1  1  0.67  0.67  0.67  1.0
  Au  Au0  1  0.5  0.5  0.5  1.0

data_Sr2PtAu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   12.7
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Sr2PtAu
_chemical_formula_sum   'Sr6 Pt3 Au3'
_cell_volume   295.85
_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  0.0  1.0
  Sr  Sr1  3  0.0  0.0  0.17  1.0
  Pt  Pt2  3  0.0  0.0  0.33  1.0
  Au  Au3  3  0.0  0.0  0.5  1.0

Sr Sr Pt Au
Sr2PtAu crystallizes in the trigonal R3m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted single-bond geometry to one Sr(2), one Pt(1), and three equivalent Au(1) atoms. The Sr(1)-Sr(2) bond length is 2.12 Å. The Sr(1)-Pt(1) bond length is 2.12 Å. All Sr(1)-Au(1) bond lengths are 2.99 Å. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Sr(1), three equivalent Pt(1), and three equivalent Au(1) atoms. All Sr(2)-Pt(1) bond lengths are 2.99 Å. All Sr(2)-Au(1) bond lengths are 3.67 Å. Pt(1) is bonded to one Sr(1), three equivalent Sr(2), and one Au(1) atom to form distorted PtSr4Au trigonal bipyramids that share corners with six equivalent Pt(1)Sr4Au trigonal bipyramids, corners with three equivalent Au(1)Sr6Pt trigonal pyramids, and faces with three equivalent Au(1)Sr6Pt trigonal pyramids. The Pt(1)-Au(1) bond length is 2.12 Å. Au(1) is bonded to three equivalent Sr(1), three equivalent Sr(2), and one Pt(1) atom to form distorted AuSr6Pt trigonal pyramids that share corners with three equivalent Pt(1)Sr4Au trigonal bipyramids, edges with six equivalent Au(1)Sr6Pt trigonal pyramids, and faces with three equivalent Pt(1)Sr4Au trigonal bipyramids.