data_LaAl2Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.05
_cell_length_b   5.05
_cell_length_c   5.05
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   LaAl2Hg
_chemical_formula_sum   'La1 Al2 Hg1'
_cell_volume   90.81
_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
  La  La3  1  0.0  0.0  0.0  1.0
  Al  Al0  1  0.35  0.35  0.35  1.0
  Al  Al1  1  0.78  0.78  0.78  1.0
  Hg  Hg2  1  0.57  0.57  0.57  1.0

data_LaAl2Hg
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.05
_cell_length_b   5.05
_cell_length_c   12.36
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   LaAl2Hg
_chemical_formula_sum   'La3 Al6 Hg3'
_cell_volume   272.43
_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
  La  La0  3  0.0  0.0  0.0  1.0
  Al  Al1  3  0.0  0.0  0.22  1.0
  Al  Al2  3  0.0  0.0  0.65  1.0
  Hg  Hg3  3  0.0  0.0  0.43  1.0

La Al Al Hg
La Al Al Hg 0 2 - - - 0 2 - - o 0 2 o - - 0 2 - o - 0 3 - - o 0 3 - o - 0 3 o - - 0 1 - o o 0 1 o - o 0 1 o o - 1 3 o - o 1 3 - o o 1 3 o o - 1 3 o o o 1 2 - o o 1 2 o - o 1 2 o o - 2 3 o o o 2 3 o o + 2 3 + o o 2 3 o + o 
LaHgAl2 is Heusler structured and crystallizes in the trigonal R3m space group. La(1) is bonded in a 10-coordinate geometry to three equivalent Hg(1), three equivalent Al(1), and four equivalent Al(2) atoms. All La(1)-Hg(1) bond lengths are 3.16 Å. All La(1)-Al(1) bond lengths are 2.92 Å. There is one shorter (2.67 Å) and three longer (3.25 Å) La(1)-Al(2) bond lengths. Hg(1) is bonded in a 5-coordinate geometry to three equivalent La(1), one Al(1), and one Al(2) atom. The Hg(1)-Al(1) bond length is 2.67 Å. The Hg(1)-Al(2) bond length is 2.67 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent La(1) and one Hg(1) atom to form distorted corner-sharing AlLa3Hg trigonal pyramids. In the second Al site, Al(2) is bonded in a distorted linear geometry to four equivalent La(1) and one Hg(1) atom.