The structure described by MgHg2(BiO3)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(7), and two equivalent O(5) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to one O(3), one O(6), two equivalent O(1), and two equivalent O(8) atoms to form HgO6 octahedra that share corners with eight equivalent Bi(2)O6 octahedra and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-54°. In the second Hg site, Hg(2) is bonded in a 4-coordinate geometry to one O(2), one O(7), and two equivalent O(4) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form BiO6 octahedra that share corners with four equivalent Bi(2)O6 octahedra,  an edgeedge with one Hg(1)O6 octahedra, and  an edgeedge with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-50°. In the second Bi site, Bi(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form BiO6 octahedra that share corners with four equivalent Hg(1)O6 octahedra, corners with four equivalent Bi(1)O6 octahedra, and  an edgeedge with one Bi(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-54°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Hg(1), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded to one Mg(1), one Hg(2), and two equivalent Bi(1) atoms to form a mixture of distorted corner and face-sharing OMgHgBi2 trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Hg(1) and two equivalent Bi(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Hg(2), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Hg(1) and two equivalent Bi(2) atoms. In the seventh O site, O(7) is bonded to one Mg(1), one Hg(2), and two equivalent Bi(1) atoms to form a mixture of distorted corner and face-sharing OMgHgBi2 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Hg(1), one Bi(1), and one Bi(2) atom. is represented by the CIF card [CIF]
data_MgHg2(BiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.232
_cell_length_b   5.256
_cell_length_c   10.689
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   87.339
_symmetry_Int_Tables_number   1
_cell_volume   293.593
_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  0.732  0.745  0.500  1.0
  Hg  Hg1  1  0.025  0.025  0.000  1.0
  Hg  Hg2  1  0.366  0.368  0.500  1.0
  Bi  Bi3  1  0.014  0.013  0.315  1.0
  Bi  Bi4  1  0.014  0.013  0.685  1.0
  Bi  Bi5  1  0.524  0.523  0.160  1.0
  Bi  Bi6  1  0.524  0.523  0.840  1.0
  O  O7  1  0.214  0.809  0.832  1.0
  O  O8  1  0.214  0.809  0.168  1.0
  O  O9  1  0.154  0.798  0.500  1.0
  O  O10  1  0.342  0.342  0.000  1.0
  O  O11  1  0.308  0.307  0.307  1.0
  O  O12  1  0.308  0.307  0.693  1.0
  O  O13  1  0.715  0.716  0.318  1.0
  O  O14  1  0.715  0.716  0.682  1.0
  O  O15  1  0.704  0.703  0.000  1.0
  O  O16  1  0.795  0.150  0.500  1.0
  O  O17  1  0.810  0.215  0.169  1.0
  O  O18  1  0.810  0.215  0.831  1.0
[/CIF]
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The structure described by MgHg2(BiO3)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(7), and two equivalent O(5) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to one O(3), one O(6), two equivalent O(1), and two equivalent O(8) atoms to form HgO6 octahedra that share corners with eight equivalent Bi(2)O6 octahedra and edges with two equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-54°. In the second Hg site, Hg(2) is bonded in a 4-coordinate geometry to one O(2), one O(7), and two equivalent O(4) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form BiO6 octahedra that share corners with four equivalent Bi(2)O6 octahedra,  an edgeedge with one Hg(1)O6 octahedra, and  an edgeedge with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-50°. In the second Bi site, Bi(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form BiO6 octahedra that share corners with four equivalent Hg(1)O6 octahedra, corners with four equivalent Bi(1)O6 octahedra, and  an edgeedge with one Bi(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-54°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Hg(1), one Bi(1), and one Bi(2) atom. In the second O site, O(2) is bonded to one Mg(1), one Hg(2), and two equivalent Bi(1) atoms to form a mixture of distorted corner and face-sharing OMgHgBi2 trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Hg(1) and two equivalent Bi(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Hg(2), one Bi(1), and one Bi(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Bi(1), and one Bi(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Hg(1) and two equivalent Bi(2) atoms. In the seventh O site, O(7) is bonded to one Mg(1), one Hg(2), and two equivalent Bi(1) atoms to form a mixture of distorted corner and face-sharing OMgHgBi2 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Hg(1), one Bi(1), and one Bi(2) atom. is represented by the CIF card [CIF]
data_MgHg2(BiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.232
_cell_length_b   5.256
_cell_length_c   10.689
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   87.339
_symmetry_Int_Tables_number   1
_cell_volume   293.593
_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  0.732  0.745  0.500  1.0
  Hg  Hg1  1  0.025  0.025  0.000  1.0
  Hg  Hg2  1  0.366  0.368  0.500  1.0
  Bi  Bi3  1  0.014  0.013  0.315  1.0
  Bi  Bi4  1  0.014  0.013  0.685  1.0
  Bi  Bi5  1  0.524  0.523  0.160  1.0
  Bi  Bi6  1  0.524  0.523  0.840  1.0
  O  O7  1  0.214  0.809  0.832  1.0
  O  O8  1  0.214  0.809  0.168  1.0
  O  O9  1  0.154  0.798  0.500  1.0
  O  O10  1  0.342  0.342  0.000  1.0
  O  O11  1  0.308  0.307  0.307  1.0
  O  O12  1  0.308  0.307  0.693  1.0
  O  O13  1  0.715  0.716  0.318  1.0
  O  O14  1  0.715  0.716  0.682  1.0
  O  O15  1  0.704  0.703  0.000  1.0
  O  O16  1  0.795  0.150  0.500  1.0
  O  O17  1  0.810  0.215  0.169  1.0
  O  O18  1  0.810  0.215  0.831  1.0
[/CIF]
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