data_Sr4HgSb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.09
_cell_length_b   7.09
_cell_length_c   7.09
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr4HgSb
_chemical_formula_sum   'Sr4 Hg1 Sb1'
_cell_volume   252.17
_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  0.28  0.28  0.75  1.0
  Sr  Sr3  1  0.28  0.75  0.28  1.0
  Sr  Sr4  1  0.75  0.28  0.28  1.0
  Sr  Sr5  1  0.75  0.75  0.75  1.0
  Hg  Hg0  1  0.52  0.52  0.52  1.0
  Sb  Sb1  1  0.0  0.0  0.0  1.0

data_Sr4HgSb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.09
_cell_length_b   7.09
_cell_length_c   17.37
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Sr4HgSb
_chemical_formula_sum   'Sr12 Hg3 Sb3'
_cell_volume   756.52
_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  9  0.02  0.51  0.23  1.0
  Sr  Sr1  3  0.0  0.0  0.25  1.0
  Hg  Hg2  3  0.0  0.0  0.48  1.0
  Sb  Sb3  3  0.0  0.0  0.0  1.0

Sr Sr Sr Sr Hg Sb
Sr Sr Sr Sr Hg Sb 0 5 o o + 0 4 o o o 0 3 o - o 0 3 - o o 1 5 o + o 1 4 o o o 1 3 o o - 1 3 - o o 2 4 o o o 2 5 + o o 2 3 o o - 2 3 o - o 3 4 o o o 
Sr4HgSb crystallizes in the trigonal R3m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a linear geometry to two equivalent Sr(2), one Hg(1), and one Sb(1) atom. Both Sr(1)-Sr(2) bond lengths are 3.56 Å. The Sr(1)-Hg(1) bond length is 2.44 Å. The Sr(1)-Sb(1) bond length is 2.80 Å. In the second Sr site, Sr(2) is bonded to six equivalent Sr(1) and one Hg(1) atom to form distorted corner-sharing SrSr6Hg hexagonal pyramids. The Sr(2)-Hg(1) bond length is 3.98 Å. Hg(1) is bonded in a 3-coordinate geometry to one Sr(2) and three equivalent Sr(1) atoms. Sb(1) is bonded in a distorted T-shaped geometry to three equivalent Sr(1) atoms.