The compound described by Cs2HgBr4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent Br(2), three equivalent Br(1), and four equivalent Br(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Br(1), three equivalent Br(2), and four equivalent Br(3) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(1), one Br(2), and two equivalent Br(3) atoms. There are three inequivalent Br sites. In the first Br site, Br(1) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Hg(1) atom. In the second Br site, Br(2) is bonded in a 6-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Hg(1) atom. In the third Br site, Br(3) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of distorted corner, edge, and face-sharing BrCs4Hg square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2HgBr4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.978
_cell_length_b   10.390
_cell_length_c   14.092
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1168.062
_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  0.982  0.169  1.0
  Cs  Cs1  1  0.750  0.386  0.081  1.0
  Cs  Cs2  1  0.750  0.518  0.669  1.0
  Cs  Cs3  1  0.250  0.114  0.581  1.0
  Cs  Cs4  1  0.250  0.614  0.919  1.0
  Cs  Cs5  1  0.250  0.482  0.331  1.0
  Cs  Cs6  1  0.750  0.886  0.419  1.0
  Cs  Cs7  1  0.750  0.018  0.831  1.0
  Hg  Hg8  1  0.250  0.719  0.577  1.0
  Hg  Hg9  1  0.750  0.281  0.423  1.0
  Hg  Hg10  1  0.250  0.219  0.923  1.0
  Hg  Hg11  1  0.750  0.781  0.077  1.0
  Br  Br12  1  0.250  0.969  0.904  1.0
  Br  Br13  1  0.250  0.321  0.097  1.0
  Br  Br14  1  0.518  0.327  0.847  1.0
  Br  Br15  1  0.750  0.179  0.597  1.0
  Br  Br16  1  0.250  0.469  0.596  1.0
  Br  Br17  1  0.982  0.827  0.653  1.0
  Br  Br18  1  0.482  0.173  0.347  1.0
  Br  Br19  1  0.018  0.173  0.347  1.0
  Br  Br20  1  0.982  0.327  0.847  1.0
  Br  Br21  1  0.018  0.673  0.153  1.0
  Br  Br22  1  0.750  0.679  0.903  1.0
  Br  Br23  1  0.250  0.821  0.403  1.0
  Br  Br24  1  0.750  0.031  0.096  1.0
  Br  Br25  1  0.518  0.827  0.653  1.0
  Br  Br26  1  0.750  0.531  0.404  1.0
  Br  Br27  1  0.482  0.673  0.153  1.0
[/CIF]
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The compound described by Cs2HgBr4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent Br(2), three equivalent Br(1), and four equivalent Br(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Br(1), three equivalent Br(2), and four equivalent Br(3) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(1), one Br(2), and two equivalent Br(3) atoms. There are three inequivalent Br sites. In the first Br site, Br(1) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Hg(1) atom. In the second Br site, Br(2) is bonded in a 6-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Hg(1) atom. In the third Br site, Br(3) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of distorted corner, edge, and face-sharing BrCs4Hg square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2HgBr4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.978
_cell_length_b   10.390
_cell_length_c   14.092
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1168.062
_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  0.982  0.169  1.0
  Cs  Cs1  1  0.750  0.386  0.081  1.0
  Cs  Cs2  1  0.750  0.518  0.669  1.0
  Cs  Cs3  1  0.250  0.114  0.581  1.0
  Cs  Cs4  1  0.250  0.614  0.919  1.0
  Cs  Cs5  1  0.250  0.482  0.331  1.0
  Cs  Cs6  1  0.750  0.886  0.419  1.0
  Cs  Cs7  1  0.750  0.018  0.831  1.0
  Hg  Hg8  1  0.250  0.719  0.577  1.0
  Hg  Hg9  1  0.750  0.281  0.423  1.0
  Hg  Hg10  1  0.250  0.219  0.923  1.0
  Hg  Hg11  1  0.750  0.781  0.077  1.0
  Br  Br12  1  0.250  0.969  0.904  1.0
  Br  Br13  1  0.250  0.321  0.097  1.0
  Br  Br14  1  0.518  0.327  0.847  1.0
  Br  Br15  1  0.750  0.179  0.597  1.0
  Br  Br16  1  0.250  0.469  0.596  1.0
  Br  Br17  1  0.982  0.827  0.653  1.0
  Br  Br18  1  0.482  0.173  0.347  1.0
  Br  Br19  1  0.018  0.173  0.347  1.0
  Br  Br20  1  0.982  0.327  0.847  1.0
  Br  Br21  1  0.018  0.673  0.153  1.0
  Br  Br22  1  0.750  0.679  0.903  1.0
  Br  Br23  1  0.250  0.821  0.403  1.0
  Br  Br24  1  0.750  0.031  0.096  1.0
  Br  Br25  1  0.518  0.827  0.653  1.0
  Br  Br26  1  0.750  0.531  0.404  1.0
  Br  Br27  1  0.482  0.673  0.153  1.0
[/CIF]
.