The crystal structure described by MgHg2(WO4)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent W(1)O6 octahedra, and edges with two equivalent W(2)O6 octahedra. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form WO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent W(2)O6 octahedra. In the second W site, W(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form WO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent W(1)O6 octahedra. Hg(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form HgO4 trigonal pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent W(1)O6 octahedra, and corners with three equivalent W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-72°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one W(2), and one Hg(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(1), one W(1), and one Hg(1) atom. In the third O site, O(3) is bonded to one Mg(1), one W(1), one W(2), and one Hg(1) atom to form a mixture of corner and edge-sharing OMgHgW2 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one W(1), one W(2), and one Hg(1) atom. is represented by the CIF file [CIF]
data_MgHg2(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.450
_cell_length_b   6.259
_cell_length_c   6.706
_cell_angle_alpha   117.815
_cell_angle_beta   111.377
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   184.335
_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  0.750  0.597  0.000  1.0
  Hg  Hg1  1  0.052  0.152  0.592  1.0
  Hg  Hg2  1  0.448  0.560  0.408  1.0
  W  W3  1  0.250  0.842  0.000  1.0
  W  W4  1  0.750  0.128  0.000  1.0
  O  O5  1  0.970  0.447  0.224  1.0
  O  O6  1  0.530  0.222  0.776  1.0
  O  O7  1  0.981  0.542  0.796  1.0
  O  O8  1  0.519  0.746  0.204  1.0
  O  O9  1  0.005  0.960  0.193  1.0
  O  O10  1  0.495  0.767  0.807  1.0
  O  O11  1  0.986  0.993  0.812  1.0
  O  O12  1  0.514  0.180  0.188  1.0
[/CIF]
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The crystal structure described by MgHg2(WO4)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent W(1)O6 octahedra, and edges with two equivalent W(2)O6 octahedra. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form WO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent W(2)O6 octahedra. In the second W site, W(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form WO6 octahedra that share corners with six equivalent Hg(1)O4 trigonal pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent W(1)O6 octahedra. Hg(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form HgO4 trigonal pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent W(1)O6 octahedra, and corners with three equivalent W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-72°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one W(2), and one Hg(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(1), one W(1), and one Hg(1) atom. In the third O site, O(3) is bonded to one Mg(1), one W(1), one W(2), and one Hg(1) atom to form a mixture of corner and edge-sharing OMgHgW2 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one W(1), one W(2), and one Hg(1) atom. is represented by the CIF file [CIF]
data_MgHg2(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.450
_cell_length_b   6.259
_cell_length_c   6.706
_cell_angle_alpha   117.815
_cell_angle_beta   111.377
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   184.335
_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  0.750  0.597  0.000  1.0
  Hg  Hg1  1  0.052  0.152  0.592  1.0
  Hg  Hg2  1  0.448  0.560  0.408  1.0
  W  W3  1  0.250  0.842  0.000  1.0
  W  W4  1  0.750  0.128  0.000  1.0
  O  O5  1  0.970  0.447  0.224  1.0
  O  O6  1  0.530  0.222  0.776  1.0
  O  O7  1  0.981  0.542  0.796  1.0
  O  O8  1  0.519  0.746  0.204  1.0
  O  O9  1  0.005  0.960  0.193  1.0
  O  O10  1  0.495  0.767  0.807  1.0
  O  O11  1  0.986  0.993  0.812  1.0
  O  O12  1  0.514  0.180  0.188  1.0
[/CIF]
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