data_Mn2AlHg
_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   144.98
_cell_angle_beta   128.28
_cell_angle_gamma   64.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2AlHg
_chemical_formula_sum   'Mn2 Al1 Hg1'
_cell_volume   57.23
_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
  Mn  Mn2  1  0.0  0.0  0.24  1.0
  Mn  Mn3  1  0.52  0.0  0.97  1.0
  Al  Al0  1  0.0  0.0  0.14  1.0
  Hg  Hg1  1  0.0  0.2  0.2  1.0

data_Mn2AlHg
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.04
_cell_length_b   4.4
_cell_length_c   5.05
_cell_angle_alpha   115.86
_cell_angle_beta   107.51
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2AlHg
_chemical_formula_sum   'Mn2 Al1 Hg1'
_cell_volume   57.23
_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
  Mn  Mn0  1  0.55  0.03  0.55  1.0
  Mn  Mn1  1  0.76  0.76  0.76  1.0
  Al  Al2  1  0.86  0.86  0.86  1.0
  Hg  Hg3  1  0.8  1.0  1.0  1.0

Mn Mn Al Hg
Mn Mn Al Hg 0 2 o o o 0 1 - o - 1 3 + o + 1 2 + o + 2 3 o o o 
Mn2HgAl crystallizes in the triclinic P1 space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a single-bond geometry to two equivalent Mn(2) and one Al(1) atom. There is one shorter (1.91 Å) and one longer (2.91 Å) Mn(1)-Mn(2) bond length. The Mn(1)-Al(1) bond length is 0.51 Å. In the second Mn site, Mn(2) is bonded in a 8-coordinate geometry to two equivalent Mn(1), two equivalent Mn(2), three equivalent Hg(1), and one Al(1) atom. Both Mn(2)-Mn(2) bond lengths are 3.04 Å. There are a spread of Mn(2)-Hg(1) bond distances ranging from 2.24-3.04 Å. The Mn(2)-Al(1) bond length is 2.01 Å. Hg(1) is bonded in a single-bond geometry to three equivalent Mn(2) and one Al(1) atom. The Hg(1)-Al(1) bond length is 0.78 Å. Al(1) is bonded in a distorted bent 120 degrees geometry to one Mn(1), one Mn(2), and one Hg(1) atom.