The material described by Hg2CdSeO6 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to one O(2) and one O(6) atom. In the second Hg site, Hg(2) is bonded in a distorted linear geometry to one O(2) and one O(6) atom. Cd(1) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form CdO6 octahedra that share corners with three equivalent Se(1)O4 tetrahedra and  an edgeedge with one Cd(1)O6 octahedra. Se(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SeO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cd(1) and one Se(1) atom. In the second O site, O(2) is bonded to one Hg(1), one Hg(2), and two equivalent Cd(1) atoms to form edge-sharing OCd2Hg2 tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one 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. In the fifth O site, O(5) is bonded in a single-bond geometry to one Se(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Hg(1), one Hg(2), and one Cd(1) atom. is represented by the CIF card [CIF]
data_CdHg2SeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.023
_cell_length_b   7.355
_cell_length_c   7.695
_cell_angle_alpha   74.430
_cell_angle_beta   68.550
_cell_angle_gamma   64.294
_symmetry_Int_Tables_number   1
_cell_volume   330.443
_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  0.334  0.137  0.212  1.0
  Cd  Cd1  1  0.666  0.863  0.788  1.0
  Hg  Hg2  1  0.844  0.644  0.209  1.0
  Hg  Hg3  1  0.156  0.356  0.791  1.0
  Hg  Hg4  1  0.658  0.359  0.792  1.0
  Hg  Hg5  1  0.342  0.641  0.208  1.0
  Se  Se6  1  0.797  0.134  0.313  1.0
  Se  Se7  1  0.203  0.866  0.687  1.0
  O  O8  1  0.636  0.206  0.170  1.0
  O  O9  1  0.450  0.197  0.862  1.0
  O  O10  1  0.942  0.921  0.831  1.0
  O  O11  1  0.779  0.921  0.455  1.0
  O  O12  1  0.278  0.674  0.570  1.0
  O  O13  1  0.153  0.477  0.243  1.0
  O  O14  1  0.221  0.079  0.545  1.0
  O  O15  1  0.550  0.803  0.138  1.0
  O  O16  1  0.364  0.794  0.830  1.0
  O  O17  1  0.847  0.523  0.757  1.0
  O  O18  1  0.722  0.326  0.430  1.0
  O  O19  1  0.058  0.079  0.169  1.0
[/CIF]
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The material described by Hg2CdSeO6 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to one O(2) and one O(6) atom. In the second Hg site, Hg(2) is bonded in a distorted linear geometry to one O(2) and one O(6) atom. Cd(1) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form CdO6 octahedra that share corners with three equivalent Se(1)O4 tetrahedra and  an edgeedge with one Cd(1)O6 octahedra. Se(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SeO4 tetrahedra that share corners with three equivalent Cd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Cd(1) and one Se(1) atom. In the second O site, O(2) is bonded to one Hg(1), one Hg(2), and two equivalent Cd(1) atoms to form edge-sharing OCd2Hg2 tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one 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. In the fifth O site, O(5) is bonded in a single-bond geometry to one Se(1) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Hg(1), one Hg(2), and one Cd(1) atom. is represented by the CIF card [CIF]
data_CdHg2SeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.023
_cell_length_b   7.355
_cell_length_c   7.695
_cell_angle_alpha   74.430
_cell_angle_beta   68.550
_cell_angle_gamma   64.294
_symmetry_Int_Tables_number   1
_cell_volume   330.443
_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  0.334  0.137  0.212  1.0
  Cd  Cd1  1  0.666  0.863  0.788  1.0
  Hg  Hg2  1  0.844  0.644  0.209  1.0
  Hg  Hg3  1  0.156  0.356  0.791  1.0
  Hg  Hg4  1  0.658  0.359  0.792  1.0
  Hg  Hg5  1  0.342  0.641  0.208  1.0
  Se  Se6  1  0.797  0.134  0.313  1.0
  Se  Se7  1  0.203  0.866  0.687  1.0
  O  O8  1  0.636  0.206  0.170  1.0
  O  O9  1  0.450  0.197  0.862  1.0
  O  O10  1  0.942  0.921  0.831  1.0
  O  O11  1  0.779  0.921  0.455  1.0
  O  O12  1  0.278  0.674  0.570  1.0
  O  O13  1  0.153  0.477  0.243  1.0
  O  O14  1  0.221  0.079  0.545  1.0
  O  O15  1  0.550  0.803  0.138  1.0
  O  O16  1  0.364  0.794  0.830  1.0
  O  O17  1  0.847  0.523  0.757  1.0
  O  O18  1  0.722  0.326  0.430  1.0
  O  O19  1  0.058  0.079  0.169  1.0
[/CIF]
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