The material structure described by MgHg2(BiO3)2 crystallizes in the trigonal R3 space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MgO6 octahedra that share corners with three equivalent Hg(1)O6 octahedra, edges with three equivalent Bi(1)O6 octahedra, and  a faceface with one Hg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted HgO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Bi(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-58°. In the second Hg site, Hg(2) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted BiO6 octahedra that share corners with three equivalent Hg(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, and  a faceface with one Hg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Hg(1), one Hg(2), and one Bi(1) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Hg(1), one Bi(1), and one Bi(2) atom. is represented by the CIF card [CIF]
data_MgHg2(BiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.825
_cell_length_b   6.780
_cell_length_c   5.825
_cell_angle_alpha   115.442
_cell_angle_beta   60.000
_cell_angle_gamma   115.442
_symmetry_Int_Tables_number   1
_cell_volume   172.980
_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  0.350  0.050  0.350  1.0
  Hg  Hg1  1  0.178  0.534  0.178  1.0
  Hg  Hg2  1  0.743  0.230  0.743  1.0
  Bi  Bi3  1  0.996  0.989  0.996  1.0
  Bi  Bi4  1  0.543  0.629  0.543  1.0
  O  O5  1  0.131  0.242  0.359  1.0
  O  O6  1  0.324  0.823  0.954  1.0
  O  O7  1  0.545  0.823  0.324  1.0
  O  O8  1  0.359  0.242  0.752  1.0
  O  O9  1  0.752  0.242  0.131  1.0
  O  O10  1  0.954  0.823  0.545  1.0
[/CIF]
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The material structure described by MgHg2(BiO3)2 crystallizes in the trigonal R3 space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form MgO6 octahedra that share corners with three equivalent Hg(1)O6 octahedra, edges with three equivalent Bi(1)O6 octahedra, and  a faceface with one Hg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 36°. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted HgO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Bi(1)O6 octahedra,  a faceface with one Mg(1)O6 octahedra, and  a faceface with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 36-58°. In the second Hg site, Hg(2) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted BiO6 octahedra that share corners with three equivalent Hg(1)O6 octahedra, edges with three equivalent Mg(1)O6 octahedra, and  a faceface with one Hg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Hg(1), one Hg(2), and one Bi(1) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Hg(1), one Bi(1), and one Bi(2) atom. is represented by the CIF card [CIF]
data_MgHg2(BiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.825
_cell_length_b   6.780
_cell_length_c   5.825
_cell_angle_alpha   115.442
_cell_angle_beta   60.000
_cell_angle_gamma   115.442
_symmetry_Int_Tables_number   1
_cell_volume   172.980
_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  0.350  0.050  0.350  1.0
  Hg  Hg1  1  0.178  0.534  0.178  1.0
  Hg  Hg2  1  0.743  0.230  0.743  1.0
  Bi  Bi3  1  0.996  0.989  0.996  1.0
  Bi  Bi4  1  0.543  0.629  0.543  1.0
  O  O5  1  0.131  0.242  0.359  1.0
  O  O6  1  0.324  0.823  0.954  1.0
  O  O7  1  0.545  0.823  0.324  1.0
  O  O8  1  0.359  0.242  0.752  1.0
  O  O9  1  0.752  0.242  0.131  1.0
  O  O10  1  0.954  0.823  0.545  1.0
[/CIF]
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