The structure described by HgCdSeO6 crystallizes in the monoclinic C2/m space group. Hg(1) is bonded in a linear geometry to two equivalent O(1) atoms. Cd(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CdO6 octahedra that share corners with four equivalent Se(1)O4 tetrahedra and  an edgeedge with one Cd(1)O6 octahedra. Se(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form SeO4 tetrahedra that share corners with four equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Hg(1) and one Cd(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cd(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cd(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_CdHgSeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.176
_cell_length_b   6.934
_cell_length_c   6.934
_cell_angle_alpha   83.252
_cell_angle_beta   84.254
_cell_angle_gamma   84.254
_symmetry_Int_Tables_number   1
_cell_volume   292.249
_cell_formula_units_Z   2
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
  Cd  Cd0  1  0.500  0.698  0.302  1.0
  Cd  Cd1  1  0.500  0.302  0.698  1.0
  Hg  Hg2  1  0.000  0.500  0.000  1.0
  Hg  Hg3  1  0.000  0.000  0.500  1.0
  Se  Se4  1  0.488  0.200  0.200  1.0
  Se  Se5  1  0.512  0.800  0.800  1.0
  O  O6  1  0.870  0.577  0.267  1.0
  O  O7  1  0.870  0.267  0.577  1.0
  O  O8  1  0.130  0.423  0.733  1.0
  O  O9  1  0.130  0.733  0.423  1.0
  O  O10  1  0.241  0.156  0.156  1.0
  O  O11  1  0.759  0.844  0.844  1.0
  O  O12  1  0.472  0.364  0.364  1.0
  O  O13  1  0.528  0.636  0.636  1.0
  O  O14  1  0.629  0.296  0.996  1.0
  O  O15  1  0.629  0.996  0.296  1.0
  O  O16  1  0.371  0.704  0.004  1.0
  O  O17  1  0.371  0.004  0.704  1.0
[/CIF]
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The structure described by HgCdSeO6 crystallizes in the monoclinic C2/m space group. Hg(1) is bonded in a linear geometry to two equivalent O(1) atoms. Cd(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted CdO6 octahedra that share corners with four equivalent Se(1)O4 tetrahedra and  an edgeedge with one Cd(1)O6 octahedra. Se(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form SeO4 tetrahedra that share corners with four equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Hg(1) and one Cd(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cd(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cd(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_CdHgSeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.176
_cell_length_b   6.934
_cell_length_c   6.934
_cell_angle_alpha   83.252
_cell_angle_beta   84.254
_cell_angle_gamma   84.254
_symmetry_Int_Tables_number   1
_cell_volume   292.249
_cell_formula_units_Z   2
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
  Cd  Cd0  1  0.500  0.698  0.302  1.0
  Cd  Cd1  1  0.500  0.302  0.698  1.0
  Hg  Hg2  1  0.000  0.500  0.000  1.0
  Hg  Hg3  1  0.000  0.000  0.500  1.0
  Se  Se4  1  0.488  0.200  0.200  1.0
  Se  Se5  1  0.512  0.800  0.800  1.0
  O  O6  1  0.870  0.577  0.267  1.0
  O  O7  1  0.870  0.267  0.577  1.0
  O  O8  1  0.130  0.423  0.733  1.0
  O  O9  1  0.130  0.733  0.423  1.0
  O  O10  1  0.241  0.156  0.156  1.0
  O  O11  1  0.759  0.844  0.844  1.0
  O  O12  1  0.472  0.364  0.364  1.0
  O  O13  1  0.528  0.636  0.636  1.0
  O  O14  1  0.629  0.296  0.996  1.0
  O  O15  1  0.629  0.996  0.296  1.0
  O  O16  1  0.371  0.704  0.004  1.0
  O  O17  1  0.371  0.004  0.704  1.0
[/CIF]
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