The structure described by Mg5Hg crystallizes in the monoclinic Cm space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(5), and two equivalent Hg(1) atoms to form a mixture of distorted face and corner-sharing MgMg10Hg2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted single-bond geometry to two equivalent Mg(1), two equivalent Mg(4), and one Hg(1) atom. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Hg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Hg(1) atoms. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to two equivalent Mg(4), three equivalent Mg(1), and two equivalent Hg(1) atoms. Hg(1) is bonded in a 10-coordinate geometry to one Mg(2), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(4) atoms. is represented by the CIF file [CIF]
data_Mg5Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.955
_cell_length_b   5.955
_cell_length_c   7.239
_cell_angle_alpha   75.897
_cell_angle_beta   75.897
_cell_angle_gamma   31.612
_symmetry_Int_Tables_number   1
_cell_volume   130.167
_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  0.279  0.279  0.944  1.0
  Mg  Mg1  1  0.667  0.667  0.669  1.0
  Mg  Mg2  1  0.952  0.952  0.596  1.0
  Mg  Mg3  1  0.323  0.323  0.336  1.0
  Mg  Mg4  1  0.002  0.002  0.011  1.0
  Hg  Hg5  1  0.610  0.610  0.277  1.0
[/CIF]
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The structure described by Mg5Hg crystallizes in the monoclinic Cm space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), three equivalent Mg(5), and two equivalent Hg(1) atoms to form a mixture of distorted face and corner-sharing MgMg10Hg2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a distorted single-bond geometry to two equivalent Mg(1), two equivalent Mg(4), and one Hg(1) atom. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Hg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Hg(1) atoms. In the fifth Mg site, Mg(5) is bonded in a 2-coordinate geometry to two equivalent Mg(4), three equivalent Mg(1), and two equivalent Hg(1) atoms. Hg(1) is bonded in a 10-coordinate geometry to one Mg(2), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(4) atoms. is represented by the CIF file [CIF]
data_Mg5Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.955
_cell_length_b   5.955
_cell_length_c   7.239
_cell_angle_alpha   75.897
_cell_angle_beta   75.897
_cell_angle_gamma   31.612
_symmetry_Int_Tables_number   1
_cell_volume   130.167
_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  0.279  0.279  0.944  1.0
  Mg  Mg1  1  0.667  0.667  0.669  1.0
  Mg  Mg2  1  0.952  0.952  0.596  1.0
  Mg  Mg3  1  0.323  0.323  0.336  1.0
  Mg  Mg4  1  0.002  0.002  0.011  1.0
  Hg  Hg5  1  0.610  0.610  0.277  1.0
[/CIF]
.