data_ZnCrHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.48
_cell_length_b   4.48
_cell_length_c   4.48
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZnCrHg
_chemical_formula_sum   'Zn1 Cr1 Hg1'
_cell_volume   63.7
_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
  Zn  Zn2  1  0.75  0.75  0.75  1.0
  Cr  Cr0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.58  0.58  0.58  1.0

data_ZnCrHg
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.48
_cell_length_b   4.48
_cell_length_c   10.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ZnCrHg
_chemical_formula_sum   'Zn3 Cr3 Hg3'
_cell_volume   191.1
_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
  Zn  Zn0  3  0.0  0.0  0.25  1.0
  Cr  Cr1  3  0.0  0.0  0.0  1.0
  Hg  Hg2  3  0.0  0.0  0.42  1.0

Zn Cr Hg
Zn Cr Hg 0 2 o o o 0 1 + + + 0 1 + + o 0 1 o + + 0 1 + o + 1 2 - - o 1 2 - o - 1 2 o - - 
CrHgZn is half-Heusler structured and crystallizes in the trigonal R3m space group. Cr(1) is bonded in a 7-coordinate geometry to three equivalent Hg(1) and four equivalent Zn(1) atoms. All Cr(1)-Hg(1) bond lengths are 2.74 Å. There is one shorter (2.69 Å) and three longer (2.76 Å) Cr(1)-Zn(1) bond lengths. Hg(1) is bonded in a distorted single-bond geometry to three equivalent Cr(1) and one Zn(1) atom. The Hg(1)-Zn(1) bond length is 1.86 Å. Zn(1) is bonded in a single-bond geometry to four equivalent Cr(1) and one Hg(1) atom.