The material structure described by Hg3Se2I2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted see-saw-like geometry to one Se(1), one Se(2), one I(1), and one I(2) atom. In the second Hg site, Hg(2) is bonded in a distorted rectangular see-saw-like geometry to one Se(1), one Se(2), one I(3), and one I(4) atom. In the third Hg site, Hg(3,4) is bonded in a distorted see-saw-like geometry to two equivalent Se(1), one I(1), and one I(4) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one Hg(1); one Hg(2); and one Hg(3,4) atom. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Hg(1); one Hg(2); and one Hg(3,4) atom. There are four inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Hg(3,4) and two equivalent Hg(1) atoms. In the second I site, I(2) is bonded in a trigonal non-coplanar geometry to one Hg(3,4) and two equivalent Hg(1) atoms. In the third I site, I(3) is bonded in an L-shaped geometry to two equivalent Hg(2) atoms. In the fourth I site, I(4) is bonded in a tetrahedral geometry to two equivalent Hg(2) and two equivalent Hg(3,4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hg3(SeI)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.107
_cell_length_b   12.105
_cell_length_c   12.107
_cell_angle_alpha   132.238
_cell_angle_beta   131.511
_cell_angle_gamma   70.428
_symmetry_Int_Tables_number   1
_cell_volume   963.945
_cell_formula_units_Z   4
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
  Hg  Hg0  1  0.151  0.651  0.000  1.0
  Hg  Hg1  1  0.349  0.349  0.500  1.0
  Hg  Hg2  1  0.849  0.349  0.000  1.0
  Hg  Hg3  1  0.651  0.651  0.500  1.0
  Hg  Hg4  1  0.026  0.746  0.272  1.0
  Hg  Hg5  1  0.474  0.746  0.720  1.0
  Hg  Hg6  1  0.526  0.254  0.280  1.0
  Hg  Hg7  1  0.974  0.254  0.728  1.0
  Hg  Hg8  1  0.118  0.074  0.957  1.0
  Hg  Hg9  1  0.382  0.339  0.957  1.0
  Hg  Hg10  1  0.882  0.926  0.043  1.0
  Hg  Hg11  1  0.618  0.661  0.043  1.0
  Se  Se12  1  0.132  0.885  0.261  1.0
  Se  Se13  1  0.368  0.630  0.754  1.0
  Se  Se14  1  0.376  0.115  0.246  1.0
  Se  Se15  1  0.124  0.371  0.739  1.0
  Se  Se16  1  0.868  0.115  0.739  1.0
  Se  Se17  1  0.632  0.370  0.246  1.0
  Se  Se18  1  0.624  0.885  0.754  1.0
  Se  Se19  1  0.876  0.629  0.261  1.0
  I  I20  1  0.999  0.745  0.746  1.0
  I  I21  1  0.501  0.246  0.746  1.0
  I  I22  1  0.000  0.255  0.254  1.0
  I  I23  1  0.499  0.754  0.254  1.0
  I  I24  1  0.750  0.493  0.742  1.0
  I  I25  1  0.250  0.508  0.258  1.0
  I  I26  1  0.750  0.003  0.253  1.0
  I  I27  1  0.250  0.997  0.747  1.0
[/CIF]
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The material structure described by Hg3Se2I2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted see-saw-like geometry to one Se(1), one Se(2), one I(1), and one I(2) atom. In the second Hg site, Hg(2) is bonded in a distorted rectangular see-saw-like geometry to one Se(1), one Se(2), one I(3), and one I(4) atom. In the third Hg site, Hg(3,4) is bonded in a distorted see-saw-like geometry to two equivalent Se(1), one I(1), and one I(4) atom. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to one Hg(1); one Hg(2); and one Hg(3,4) atom. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Hg(1); one Hg(2); and one Hg(3,4) atom. There are four inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Hg(3,4) and two equivalent Hg(1) atoms. In the second I site, I(2) is bonded in a trigonal non-coplanar geometry to one Hg(3,4) and two equivalent Hg(1) atoms. In the third I site, I(3) is bonded in an L-shaped geometry to two equivalent Hg(2) atoms. In the fourth I site, I(4) is bonded in a tetrahedral geometry to two equivalent Hg(2) and two equivalent Hg(3,4) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hg3(SeI)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.107
_cell_length_b   12.105
_cell_length_c   12.107
_cell_angle_alpha   132.238
_cell_angle_beta   131.511
_cell_angle_gamma   70.428
_symmetry_Int_Tables_number   1
_cell_volume   963.945
_cell_formula_units_Z   4
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
  Hg  Hg0  1  0.151  0.651  0.000  1.0
  Hg  Hg1  1  0.349  0.349  0.500  1.0
  Hg  Hg2  1  0.849  0.349  0.000  1.0
  Hg  Hg3  1  0.651  0.651  0.500  1.0
  Hg  Hg4  1  0.026  0.746  0.272  1.0
  Hg  Hg5  1  0.474  0.746  0.720  1.0
  Hg  Hg6  1  0.526  0.254  0.280  1.0
  Hg  Hg7  1  0.974  0.254  0.728  1.0
  Hg  Hg8  1  0.118  0.074  0.957  1.0
  Hg  Hg9  1  0.382  0.339  0.957  1.0
  Hg  Hg10  1  0.882  0.926  0.043  1.0
  Hg  Hg11  1  0.618  0.661  0.043  1.0
  Se  Se12  1  0.132  0.885  0.261  1.0
  Se  Se13  1  0.368  0.630  0.754  1.0
  Se  Se14  1  0.376  0.115  0.246  1.0
  Se  Se15  1  0.124  0.371  0.739  1.0
  Se  Se16  1  0.868  0.115  0.739  1.0
  Se  Se17  1  0.632  0.370  0.246  1.0
  Se  Se18  1  0.624  0.885  0.754  1.0
  Se  Se19  1  0.876  0.629  0.261  1.0
  I  I20  1  0.999  0.745  0.746  1.0
  I  I21  1  0.501  0.246  0.746  1.0
  I  I22  1  0.000  0.255  0.254  1.0
  I  I23  1  0.499  0.754  0.254  1.0
  I  I24  1  0.750  0.493  0.742  1.0
  I  I25  1  0.250  0.508  0.258  1.0
  I  I26  1  0.750  0.003  0.253  1.0
  I  I27  1  0.250  0.997  0.747  1.0
[/CIF]
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