data_AlHg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.54
_cell_length_b   5.54
_cell_length_c   3.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   111.44
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AlHg3
_chemical_formula_sum   'Al1 Hg3'
_cell_volume   94.34
_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
  Al  Al0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.56  0.29  0.65  1.0
  Hg  Hg2  1  0.56  0.71  0.65  1.0
  Hg  Hg3  1  0.12  0.0  0.0  1.0

data_AlHg3
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.3
_cell_length_b   5.54
_cell_length_c   5.54
_cell_angle_alpha   111.44
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AlHg3
_chemical_formula_sum   'Al1 Hg3'
_cell_volume   94.34
_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
  Al  Al0  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.0  0.12  0.0  1.0
  Hg  Hg2  1  0.65  0.56  0.29  1.0
  Hg  Hg3  1  0.65  0.56  0.71  1.0

Al Hg Hg Hg
Al Hg Hg Hg 0 3 o o o 0 2 - - - 1 3 o o + 1 2 o o o 
Hg3Al crystallizes in the triclinic P1 space group. There are three inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a 6-coordinate geometry to two equivalent Hg(1), two equivalent Hg(2), and two equivalent Hg(3) atoms. Both Hg(1)-Hg(1) bond lengths are 3.30 Å. There is one shorter (2.35 Å) and one longer (3.19 Å) Hg(1)-Hg(2) bond length. There is one shorter (2.64 Å) and one longer (3.21 Å) Hg(1)-Hg(3) bond length. In the second Hg site, Hg(2) is bonded in a 2-coordinate geometry to two equivalent Hg(1) and one Al(1) atom. The Hg(2)-Al(1) bond length is 2.64 Å. In the third Hg site, Hg(3) is bonded in a single-bond geometry to two equivalent Hg(1) and one Al(1) atom. The Hg(3)-Al(1) bond length is 0.66 Å. Al(1) is bonded in a single-bond geometry to one Hg(2) and one Hg(3) atom.