data_MgFeHg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.17
_cell_length_b   4.82
_cell_length_c   4.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgFeHg2
_chemical_formula_sum   'Mg1 Fe1 Hg2'
_cell_volume   75.8
_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
  Mg  Mg3  1  0.0  0.0  0.83  1.0
  Fe  Fe0  1  0.0  0.41  0.87  1.0
  Hg  Hg1  1  0.59  0.0  0.42  1.0
  Hg  Hg2  1  0.59  0.41  0.34  1.0

data_MgFeHg2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.17
_cell_length_b   4.82
_cell_length_c   4.97
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgFeHg2
_chemical_formula_sum   'Mg1 Fe1 Hg2'
_cell_volume   75.8
_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
  Mg  Mg0  1  0.0  0.0  0.83  1.0
  Fe  Fe1  1  0.0  0.41  0.87  1.0
  Hg  Hg2  1  0.59  0.0  0.42  1.0
  Hg  Hg3  1  0.59  0.41  0.34  1.0

Mg Fe Hg Hg
MgFeHg2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to two equivalent Fe(1) and three equivalent Hg(1) atoms. There is one shorter (1.98 Å) and one longer (2.86 Å) Mg(1)-Fe(1) bond length. There are a spread of Mg(1)-Hg(1) bond distances ranging from 2.43-3.21 Å. Fe(1) is bonded in a distorted single-bond geometry to two equivalent Mg(1) and four equivalent Hg(2) atoms. There are a spread of Fe(1)-Hg(2) bond distances ranging from 2.66-3.24 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a 3-coordinate geometry to three equivalent Mg(1) and two equivalent Hg(2) atoms. There is one shorter (2.00 Å) and one longer (2.88 Å) Hg(1)-Hg(2) bond length. In the second Hg site, Hg(2) is bonded in a 8-coordinate geometry to four equivalent Fe(1), two equivalent Hg(1), and two equivalent Hg(2) atoms. Both Hg(2)-Hg(2) bond lengths are 3.17 Å.