The material described by Mg3Hg crystallizes in the trigonal R32 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to one Mg(4), one Hg(1), and two equivalent Hg(2) atoms. In the second Mg site, Mg(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Hg(1) atoms. In the third Mg site, Mg(3) is bonded in a 3-coordinate geometry to one Mg(4), one Hg(2), and two equivalent Hg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 11-coordinate geometry to one Mg(4), one Mg(5), three equivalent Mg(1), three equivalent Mg(3), and three equivalent Hg(1) atoms. In the fifth Mg site, Mg(5) is bonded in a trigonal planar geometry to one Mg(4) and three equivalent Hg(2) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(3) atoms. In the second Hg site, Hg(2) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_Mg3Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.961
_cell_length_b   9.961
_cell_length_c   9.961
_cell_angle_alpha   48.957
_cell_angle_beta   48.957
_cell_angle_gamma   48.957
_symmetry_Int_Tables_number   1
_cell_volume   516.143
_cell_formula_units_Z   6
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  0.084  0.329  0.756  1.0
  Mg  Mg1  1  0.864  0.864  0.864  1.0
  Mg  Mg2  1  0.033  0.770  0.523  1.0
  Mg  Mg3  1  0.444  0.444  0.444  1.0
  Mg  Mg4  1  0.329  0.756  0.084  1.0
  Mg  Mg5  1  0.244  0.671  0.916  1.0
  Mg  Mg6  1  0.230  0.967  0.477  1.0
  Mg  Mg7  1  0.523  0.033  0.770  1.0
  Mg  Mg8  1  0.770  0.523  0.033  1.0
  Mg  Mg9  1  0.679  0.679  0.679  1.0
  Mg  Mg10  1  0.756  0.084  0.329  1.0
  Mg  Mg11  1  0.671  0.916  0.244  1.0
  Mg  Mg12  1  0.136  0.136  0.136  1.0
  Mg  Mg13  1  0.967  0.477  0.230  1.0
  Mg  Mg14  1  0.556  0.556  0.556  1.0
  Mg  Mg15  1  0.477  0.230  0.967  1.0
  Mg  Mg16  1  0.916  0.244  0.671  1.0
  Mg  Mg17  1  0.321  0.321  0.321  1.0
  Hg  Hg18  1  0.820  0.180  0.500  1.0
  Hg  Hg19  1  0.330  0.000  0.670  1.0
  Hg  Hg20  1  0.670  0.330  0.000  1.0
  Hg  Hg21  1  0.000  0.670  0.330  1.0
  Hg  Hg22  1  0.180  0.500  0.820  1.0
  Hg  Hg23  1  0.500  0.820  0.180  1.0
[/CIF]
.
The material described by Mg3Hg crystallizes in the trigonal R32 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to one Mg(4), one Hg(1), and two equivalent Hg(2) atoms. In the second Mg site, Mg(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Hg(1) atoms. In the third Mg site, Mg(3) is bonded in a 3-coordinate geometry to one Mg(4), one Hg(2), and two equivalent Hg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 11-coordinate geometry to one Mg(4), one Mg(5), three equivalent Mg(1), three equivalent Mg(3), and three equivalent Hg(1) atoms. In the fifth Mg site, Mg(5) is bonded in a trigonal planar geometry to one Mg(4) and three equivalent Hg(2) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(3) atoms. In the second Hg site, Hg(2) is bonded in a 8-coordinate geometry to two equivalent Mg(3), two equivalent Mg(5), and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_Mg3Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.961
_cell_length_b   9.961
_cell_length_c   9.961
_cell_angle_alpha   48.957
_cell_angle_beta   48.957
_cell_angle_gamma   48.957
_symmetry_Int_Tables_number   1
_cell_volume   516.143
_cell_formula_units_Z   6
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  0.084  0.329  0.756  1.0
  Mg  Mg1  1  0.864  0.864  0.864  1.0
  Mg  Mg2  1  0.033  0.770  0.523  1.0
  Mg  Mg3  1  0.444  0.444  0.444  1.0
  Mg  Mg4  1  0.329  0.756  0.084  1.0
  Mg  Mg5  1  0.244  0.671  0.916  1.0
  Mg  Mg6  1  0.230  0.967  0.477  1.0
  Mg  Mg7  1  0.523  0.033  0.770  1.0
  Mg  Mg8  1  0.770  0.523  0.033  1.0
  Mg  Mg9  1  0.679  0.679  0.679  1.0
  Mg  Mg10  1  0.756  0.084  0.329  1.0
  Mg  Mg11  1  0.671  0.916  0.244  1.0
  Mg  Mg12  1  0.136  0.136  0.136  1.0
  Mg  Mg13  1  0.967  0.477  0.230  1.0
  Mg  Mg14  1  0.556  0.556  0.556  1.0
  Mg  Mg15  1  0.477  0.230  0.967  1.0
  Mg  Mg16  1  0.916  0.244  0.671  1.0
  Mg  Mg17  1  0.321  0.321  0.321  1.0
  Hg  Hg18  1  0.820  0.180  0.500  1.0
  Hg  Hg19  1  0.330  0.000  0.670  1.0
  Hg  Hg20  1  0.670  0.330  0.000  1.0
  Hg  Hg21  1  0.000  0.670  0.330  1.0
  Hg  Hg22  1  0.180  0.500  0.820  1.0
  Hg  Hg23  1  0.500  0.820  0.180  1.0
[/CIF]
.