data_ZrFeHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.51
_cell_length_b   4.51
_cell_length_c   4.51
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZrFeHg
_chemical_formula_sum   'Zr1 Fe1 Hg1'
_cell_volume   64.88
_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
  Zr  Zr2  1  0.59  0.59  0.59  1.0
  Fe  Fe0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.19  0.19  0.19  1.0

data_ZrFeHg
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.51
_cell_length_b   4.51
_cell_length_c   11.05
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ZrFeHg
_chemical_formula_sum   'Zr3 Fe3 Hg3'
_cell_volume   194.64
_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
  Zr  Zr0  3  0.0  0.0  0.41  1.0
  Fe  Fe1  3  0.0  0.0  0.0  1.0
  Hg  Hg2  3  0.0  0.0  0.81  1.0

Zr Fe Hg
Zr Fe Hg 0 2 o o + 0 2 o + o 0 2 + o o 0 1 o + + 0 1 + o + 0 1 + + o 1 2 o o o 
ZrFeHg crystallizes in the trigonal R3m space group. Zr(1) is bonded in a distorted hexagonal planar geometry to three equivalent Fe(1) and three equivalent Hg(1) atoms. All Zr(1)-Fe(1) bond lengths are 2.72 Å. All Zr(1)-Hg(1) bond lengths are 2.72 Å. Fe(1) is bonded to three equivalent Zr(1) and one Hg(1) atom to form distorted FeZr3Hg tetrahedra that share corners with three equivalent Hg(1)Zr3Fe tetrahedra, corners with six equivalent Fe(1)Zr3Hg tetrahedra, and edges with three equivalent Hg(1)Zr3Fe tetrahedra. The Fe(1)-Hg(1) bond length is 2.09 Å. Hg(1) is bonded to three equivalent Zr(1) and one Fe(1) atom to form distorted HgZr3Fe tetrahedra that share corners with three equivalent Fe(1)Zr3Hg tetrahedra, corners with six equivalent Hg(1)Zr3Fe tetrahedra, and edges with three equivalent Fe(1)Zr3Hg tetrahedra.