data_CaHg4Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.25
_cell_length_b   6.25
_cell_length_c   6.25
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaHg4Br
_chemical_formula_sum   'Ca1 Hg4 Br1'
_cell_volume   172.84
_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
  Ca  Ca1  1  0.0  0.0  0.0  1.0
  Hg  Hg2  1  0.53  0.53  0.32  1.0
  Hg  Hg3  1  0.53  0.32  0.53  1.0
  Hg  Hg4  1  0.32  0.53  0.53  1.0
  Hg  Hg5  1  0.32  0.32  0.32  1.0
  Br  Br0  1  0.63  0.63  0.63  1.0

data_CaHg4Br
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.25
_cell_length_b   6.25
_cell_length_c   15.32
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaHg4Br
_chemical_formula_sum   'Ca3 Hg12 Br3'
_cell_volume   518.51
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Hg  Hg1  9  0.14  0.07  0.54  1.0
  Hg  Hg2  3  0.0  0.0  0.68  1.0
  Br  Br3  3  0.0  0.0  0.37  1.0

Ca Hg Hg Hg Hg Br
Ca Hg Hg Hg Hg Br 0 1 - - o 0 1 - o o 0 1 o - o 0 5 - - o 0 5 - o - 0 5 o - - 0 2 - o - 0 2 - o o 0 2 o o - 0 4 - o o 0 4 o - o 0 4 o o - 0 3 o - - 0 3 o - o 0 3 o o - 1 2 o o o 1 3 o o o 1 4 o o o 1 5 o o o 2 3 o o o 2 4 o o o 2 5 o o o 3 4 o o o 3 5 o o o 
CaHg4Br crystallizes in the trigonal R3m space group. Ca(1) is bonded in a distorted hexagonal planar geometry to three equivalent Hg(2) and three equivalent Br(1) atoms. All Ca(1)-Hg(2) bond lengths are 3.62 Å. All Ca(1)-Br(1) bond lengths are 3.65 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a 2-coordinate geometry to one Hg(2), two equivalent Hg(1), and one Br(1) atom. The Hg(1)-Hg(2) bond length is 2.26 Å. Both Hg(1)-Hg(1) bond lengths are 1.31 Å. The Hg(1)-Br(1) bond length is 2.80 Å. In the second Hg site, Hg(2) is bonded in a 6-coordinate geometry to three equivalent Ca(1) and three equivalent Hg(1) atoms. Br(1) is bonded in a 6-coordinate geometry to three equivalent Ca(1) and three equivalent Hg(1) atoms.