The structure described by Cs2HgBr4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Br(4), two equivalent Br(1), two equivalent Br(2), and three equivalent Br(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Br(3), two equivalent Br(1), two equivalent Br(2), and three equivalent Br(4) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(1), one Br(2), one Br(3), and one Br(4) atom. There are four inequivalent Br sites. In the first Br site, Br(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of corner, face, and edge-sharing BrCs4Hg square pyramids. In the second Br site, Br(2) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of corner, face, and edge-sharing BrCs4Hg square pyramids. In the third Br site, Br(3) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Hg(1) atom. In the fourth Br site, Br(4) is bonded in a 5-coordinate geometry to one Cs(1), three equivalent Cs(2), and one Hg(1) atom. is represented by the CIF card [CIF]
data_Cs2HgBr4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.942
_cell_length_b   8.335
_cell_length_c   10.039
_cell_angle_alpha   107.724
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   633.010
_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
  Br  Br0  1  0.011  0.500  0.252  1.0
  Br  Br1  1  0.511  0.500  0.748  1.0
  Br  Br2  1  0.989  0.500  0.748  1.0
  Br  Br3  1  0.489  0.500  0.252  1.0
  Br  Br4  1  0.750  0.113  0.380  1.0
  Br  Br5  1  0.250  0.887  0.620  1.0
  Br  Br6  1  0.750  0.107  0.925  1.0
  Br  Br7  1  0.250  0.893  0.075  1.0
  Cs  Cs8  1  0.750  0.759  0.563  1.0
  Cs  Cs9  1  0.250  0.241  0.437  1.0
  Cs  Cs10  1  0.750  0.746  0.064  1.0
  Cs  Cs11  1  0.250  0.254  0.936  1.0
  Hg  Hg12  1  0.750  0.286  0.195  1.0
  Hg  Hg13  1  0.250  0.714  0.805  1.0
[/CIF]
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The structure described by Cs2HgBr4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 8-coordinate geometry to one Br(4), two equivalent Br(1), two equivalent Br(2), and three equivalent Br(3) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Br(3), two equivalent Br(1), two equivalent Br(2), and three equivalent Br(4) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(1), one Br(2), one Br(3), and one Br(4) atom. There are four inequivalent Br sites. In the first Br site, Br(1) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of corner, face, and edge-sharing BrCs4Hg square pyramids. In the second Br site, Br(2) is bonded to two equivalent Cs(1), two equivalent Cs(2), and one Hg(1) atom to form a mixture of corner, face, and edge-sharing BrCs4Hg square pyramids. In the third Br site, Br(3) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one Hg(1) atom. In the fourth Br site, Br(4) is bonded in a 5-coordinate geometry to one Cs(1), three equivalent Cs(2), and one Hg(1) atom. is represented by the CIF card [CIF]
data_Cs2HgBr4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.942
_cell_length_b   8.335
_cell_length_c   10.039
_cell_angle_alpha   107.724
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   633.010
_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
  Br  Br0  1  0.011  0.500  0.252  1.0
  Br  Br1  1  0.511  0.500  0.748  1.0
  Br  Br2  1  0.989  0.500  0.748  1.0
  Br  Br3  1  0.489  0.500  0.252  1.0
  Br  Br4  1  0.750  0.113  0.380  1.0
  Br  Br5  1  0.250  0.887  0.620  1.0
  Br  Br6  1  0.750  0.107  0.925  1.0
  Br  Br7  1  0.250  0.893  0.075  1.0
  Cs  Cs8  1  0.750  0.759  0.563  1.0
  Cs  Cs9  1  0.250  0.241  0.437  1.0
  Cs  Cs10  1  0.750  0.746  0.064  1.0
  Cs  Cs11  1  0.250  0.254  0.936  1.0
  Hg  Hg12  1  0.750  0.286  0.195  1.0
  Hg  Hg13  1  0.250  0.714  0.805  1.0
[/CIF]
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