data_SrCdCuHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   5.18
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrCdCuHg
_chemical_formula_sum   'Sr1 Cd1 Cu1 Hg1'
_cell_volume   98.44
_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  Sr3  1  0.66  0.66  0.66  1.0
  Cd  Cd0  1  0.83  0.83  0.83  1.0
  Cu  Cu1  1  0.0  0.0  0.0  1.0
  Hg  Hg2  1  0.5  0.5  0.5  1.0

data_SrCdCuHg
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.18
_cell_length_b   5.18
_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   SrCdCuHg
_chemical_formula_sum   'Sr3 Cd3 Cu3 Hg3'
_cell_volume   295.31
_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  0.34  1.0
  Cd  Cd1  3  0.0  0.0  0.17  1.0
  Cu  Cu2  3  0.0  0.0  0.0  1.0
  Hg  Hg3  3  0.0  0.0  0.5  1.0

Sr Cd Cu Hg
SrCuHgCd crystallizes in the trigonal R3m space group. Sr(1) is bonded to three equivalent Cu(1), one Hg(1), and one Cd(1) atom to form distorted SrCdCu3Hg trigonal bipyramids that share corners with six equivalent Sr(1)CdCu3Hg trigonal bipyramids,  a cornercorner with one Cu(1)Sr3Cd trigonal pyramid, and edges with three equivalent Cd(1)SrCuHg3 trigonal bipyramids. All Sr(1)-Cu(1) bond lengths are 2.99 Å. The Sr(1)-Hg(1) bond length is 2.13 Å. The Sr(1)-Cd(1) bond length is 2.13 Å. Cu(1) is bonded to three equivalent Sr(1) and one Cd(1) atom to form CuSr3Cd trigonal pyramids that share  a cornercorner with one Sr(1)CdCu3Hg trigonal bipyramid, corners with three equivalent Cd(1)SrCuHg3 trigonal bipyramids, and corners with six equivalent Cu(1)Sr3Cd trigonal pyramids. The Cu(1)-Cd(1) bond length is 2.13 Å. Hg(1) is bonded in a distorted single-bond geometry to one Sr(1) and three equivalent Cd(1) atoms. All Hg(1)-Cd(1) bond lengths are 2.99 Å. Cd(1) is bonded to one Sr(1), one Cu(1), and three equivalent Hg(1) atoms to form distorted CdSrCuHg3 trigonal bipyramids that share corners with six equivalent Cd(1)SrCuHg3 trigonal bipyramids, corners with three equivalent Cu(1)Sr3Cd trigonal pyramids, and edges with three equivalent Sr(1)CdCu3Hg trigonal bipyramids.