The crystal structure described by Cs2HgCl4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Cl(1), three equivalent Cl(2), and four equivalent Cl(3) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Cl(2), three equivalent Cl(1), and four equivalent Cl(3) atoms. Hg(1) is bonded in a tetrahedral geometry to one Cl(1), one Cl(2), and two equivalent Cl(3) atoms. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one Cs(1), three equivalent Cs(2), and one Hg(1) atom. In the second Cl site, Cl(2) is bonded to two equivalent Cs(2), three equivalent Cs(1), and one Hg(1) atom to form distorted ClCs5Hg octahedra that share corners with four equivalent Cl(2)Cs5Hg octahedra, corners with six equivalent Cl(3)Cs4Hg square pyramids, edges with two equivalent Cl(2)Cs5Hg octahedra, edges with two equivalent Cl(3)Cs4Hg square pyramids, and faces with four equivalent Cl(3)Cs4Hg square pyramids. The corner-sharing octahedral tilt angles range from 20-44°. In the third Cl site, Cl(3) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form distorted ClCs4Hg square pyramids that share corners with three equivalent Cl(2)Cs5Hg octahedra, corners with six equivalent Cl(3)Cs4Hg square pyramids,  an edgeedge with one Cl(2)Cs5Hg octahedra, edges with two equivalent Cl(3)Cs4Hg square pyramids, faces with two equivalent Cl(2)Cs5Hg octahedra, and  a faceface with one Cl(3)Cs4Hg square pyramid. The corner-sharing octahedral tilt angles range from 39-59°. is represented by the CIF file [CIF]
data_Cs2HgCl4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.573
_cell_length_b   9.948
_cell_length_c   13.672
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1030.077
_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
  Cs  Cs0  1  0.250  0.615  0.425  1.0
  Cs  Cs1  1  0.250  0.115  0.075  1.0
  Cs  Cs2  1  0.750  0.385  0.575  1.0
  Cs  Cs3  1  0.750  0.885  0.925  1.0
  Cs  Cs4  1  0.250  0.984  0.677  1.0
  Cs  Cs5  1  0.250  0.484  0.823  1.0
  Cs  Cs6  1  0.750  0.016  0.323  1.0
  Cs  Cs7  1  0.750  0.516  0.177  1.0
  Hg  Hg8  1  0.250  0.212  0.424  1.0
  Hg  Hg9  1  0.250  0.712  0.076  1.0
  Hg  Hg10  1  0.750  0.788  0.576  1.0
  Hg  Hg11  1  0.750  0.288  0.924  1.0
  Cl  Cl12  1  0.250  0.965  0.414  1.0
  Cl  Cl13  1  0.250  0.465  0.086  1.0
  Cl  Cl14  1  0.750  0.035  0.586  1.0
  Cl  Cl15  1  0.750  0.535  0.914  1.0
  Cl  Cl16  1  0.250  0.321  0.593  1.0
  Cl  Cl17  1  0.250  0.821  0.907  1.0
  Cl  Cl18  1  0.750  0.679  0.407  1.0
  Cl  Cl19  1  0.750  0.179  0.093  1.0
  Cl  Cl20  1  0.986  0.325  0.348  1.0
  Cl  Cl21  1  0.514  0.825  0.152  1.0
  Cl  Cl22  1  0.486  0.675  0.652  1.0
  Cl  Cl23  1  0.014  0.175  0.848  1.0
  Cl  Cl24  1  0.014  0.675  0.652  1.0
  Cl  Cl25  1  0.486  0.175  0.848  1.0
  Cl  Cl26  1  0.514  0.325  0.348  1.0
  Cl  Cl27  1  0.986  0.825  0.152  1.0
[/CIF]
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The crystal structure described by Cs2HgCl4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Cl(1), three equivalent Cl(2), and four equivalent Cl(3) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Cl(2), three equivalent Cl(1), and four equivalent Cl(3) atoms. Hg(1) is bonded in a tetrahedral geometry to one Cl(1), one Cl(2), and two equivalent Cl(3) atoms. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one Cs(1), three equivalent Cs(2), and one Hg(1) atom. In the second Cl site, Cl(2) is bonded to two equivalent Cs(2), three equivalent Cs(1), and one Hg(1) atom to form distorted ClCs5Hg octahedra that share corners with four equivalent Cl(2)Cs5Hg octahedra, corners with six equivalent Cl(3)Cs4Hg square pyramids, edges with two equivalent Cl(2)Cs5Hg octahedra, edges with two equivalent Cl(3)Cs4Hg square pyramids, and faces with four equivalent Cl(3)Cs4Hg square pyramids. The corner-sharing octahedral tilt angles range from 20-44°. In the third Cl site, Cl(3) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form distorted ClCs4Hg square pyramids that share corners with three equivalent Cl(2)Cs5Hg octahedra, corners with six equivalent Cl(3)Cs4Hg square pyramids,  an edgeedge with one Cl(2)Cs5Hg octahedra, edges with two equivalent Cl(3)Cs4Hg square pyramids, faces with two equivalent Cl(2)Cs5Hg octahedra, and  a faceface with one Cl(3)Cs4Hg square pyramid. The corner-sharing octahedral tilt angles range from 39-59°. is represented by the CIF file [CIF]
data_Cs2HgCl4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.573
_cell_length_b   9.948
_cell_length_c   13.672
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1030.077
_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
  Cs  Cs0  1  0.250  0.615  0.425  1.0
  Cs  Cs1  1  0.250  0.115  0.075  1.0
  Cs  Cs2  1  0.750  0.385  0.575  1.0
  Cs  Cs3  1  0.750  0.885  0.925  1.0
  Cs  Cs4  1  0.250  0.984  0.677  1.0
  Cs  Cs5  1  0.250  0.484  0.823  1.0
  Cs  Cs6  1  0.750  0.016  0.323  1.0
  Cs  Cs7  1  0.750  0.516  0.177  1.0
  Hg  Hg8  1  0.250  0.212  0.424  1.0
  Hg  Hg9  1  0.250  0.712  0.076  1.0
  Hg  Hg10  1  0.750  0.788  0.576  1.0
  Hg  Hg11  1  0.750  0.288  0.924  1.0
  Cl  Cl12  1  0.250  0.965  0.414  1.0
  Cl  Cl13  1  0.250  0.465  0.086  1.0
  Cl  Cl14  1  0.750  0.035  0.586  1.0
  Cl  Cl15  1  0.750  0.535  0.914  1.0
  Cl  Cl16  1  0.250  0.321  0.593  1.0
  Cl  Cl17  1  0.250  0.821  0.907  1.0
  Cl  Cl18  1  0.750  0.679  0.407  1.0
  Cl  Cl19  1  0.750  0.179  0.093  1.0
  Cl  Cl20  1  0.986  0.325  0.348  1.0
  Cl  Cl21  1  0.514  0.825  0.152  1.0
  Cl  Cl22  1  0.486  0.675  0.652  1.0
  Cl  Cl23  1  0.014  0.175  0.848  1.0
  Cl  Cl24  1  0.014  0.675  0.652  1.0
  Cl  Cl25  1  0.486  0.175  0.848  1.0
  Cl  Cl26  1  0.514  0.325  0.348  1.0
  Cl  Cl27  1  0.986  0.825  0.152  1.0
[/CIF]
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