The compound described by Cs3HgBr5 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 Br(3), one Br(4), two equivalent Br(1), and four equivalent Br(2) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Br(1), two equivalent Br(3), two equivalent Br(4), and three equivalent Br(2) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(3), one Br(4), and two equivalent Br(2) atoms. There are four inequivalent Br sites. In the first Br site, Br(4) is bonded in a 6-coordinate geometry to one Cs(1), four equivalent Cs(2), and one Hg(1) atom. In the second Br site, Br(1) is bonded to two equivalent Cs(1) and four equivalent Cs(2) atoms to form BrCs6 octahedra that share corners with five equivalent Br(3)Cs5Hg octahedra,  an edgeedge with one Br(3)Cs5Hg octahedra,  a faceface with one Br(3)Cs5Hg octahedra, and faces with two equivalent Br(1)Cs6 octahedra. The corner-sharing octahedral tilt angles range from 35-46°. In the third 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 fourth Br site, Br(3) is bonded to one Cs(1), four equivalent Cs(2), and one Hg(1) atom to form distorted BrCs5Hg octahedra that share corners with five equivalent Br(1)Cs6 octahedra,  an edgeedge with one Br(1)Cs6 octahedra, edges with two equivalent Br(3)Cs5Hg octahedra, and  a faceface with one Br(1)Cs6 octahedra. The corner-sharing octahedral tilt angles range from 35-46°. is represented by the CIF file [CIF]
data_Cs3HgBr5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   11.313
_cell_length_c   14.209
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1508.739
_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  0.919  0.250  0.050  1.0
  Cs  Cs1  1  0.419  0.250  0.450  1.0
  Cs  Cs2  1  0.081  0.750  0.950  1.0
  Cs  Cs3  1  0.581  0.750  0.550  1.0
  Cs  Cs4  1  0.917  0.019  0.332  1.0
  Cs  Cs5  1  0.417  0.481  0.168  1.0
  Cs  Cs6  1  0.083  0.519  0.668  1.0
  Cs  Cs7  1  0.583  0.981  0.832  1.0
  Cs  Cs8  1  0.083  0.981  0.668  1.0
  Cs  Cs9  1  0.583  0.519  0.832  1.0
  Cs  Cs10  1  0.917  0.481  0.332  1.0
  Cs  Cs11  1  0.417  0.019  0.168  1.0
  Hg  Hg12  1  0.802  0.250  0.613  1.0
  Hg  Hg13  1  0.302  0.250  0.887  1.0
  Hg  Hg14  1  0.198  0.750  0.387  1.0
  Hg  Hg15  1  0.698  0.750  0.113  1.0
  Br  Br16  1  0.671  0.250  0.262  1.0
  Br  Br17  1  0.171  0.250  0.238  1.0
  Br  Br18  1  0.329  0.750  0.738  1.0
  Br  Br19  1  0.829  0.750  0.762  1.0
  Br  Br20  1  0.687  0.048  0.565  1.0
  Br  Br21  1  0.187  0.452  0.935  1.0
  Br  Br22  1  0.313  0.548  0.435  1.0
  Br  Br23  1  0.813  0.952  0.065  1.0
  Br  Br24  1  0.313  0.952  0.435  1.0
  Br  Br25  1  0.813  0.548  0.065  1.0
  Br  Br26  1  0.687  0.452  0.565  1.0
  Br  Br27  1  0.187  0.048  0.935  1.0
  Br  Br28  1  0.542  0.250  0.991  1.0
  Br  Br29  1  0.042  0.250  0.509  1.0
  Br  Br30  1  0.458  0.750  0.009  1.0
  Br  Br31  1  0.958  0.750  0.491  1.0
  Br  Br32  1  0.877  0.250  0.792  1.0
  Br  Br33  1  0.377  0.250  0.708  1.0
  Br  Br34  1  0.123  0.750  0.208  1.0
  Br  Br35  1  0.623  0.750  0.292  1.0
[/CIF]
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The compound described by Cs3HgBr5 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 Br(3), one Br(4), two equivalent Br(1), and four equivalent Br(2) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Br(1), two equivalent Br(3), two equivalent Br(4), and three equivalent Br(2) atoms. Hg(1) is bonded in a tetrahedral geometry to one Br(3), one Br(4), and two equivalent Br(2) atoms. There are four inequivalent Br sites. In the first Br site, Br(4) is bonded in a 6-coordinate geometry to one Cs(1), four equivalent Cs(2), and one Hg(1) atom. In the second Br site, Br(1) is bonded to two equivalent Cs(1) and four equivalent Cs(2) atoms to form BrCs6 octahedra that share corners with five equivalent Br(3)Cs5Hg octahedra,  an edgeedge with one Br(3)Cs5Hg octahedra,  a faceface with one Br(3)Cs5Hg octahedra, and faces with two equivalent Br(1)Cs6 octahedra. The corner-sharing octahedral tilt angles range from 35-46°. In the third 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 fourth Br site, Br(3) is bonded to one Cs(1), four equivalent Cs(2), and one Hg(1) atom to form distorted BrCs5Hg octahedra that share corners with five equivalent Br(1)Cs6 octahedra,  an edgeedge with one Br(1)Cs6 octahedra, edges with two equivalent Br(3)Cs5Hg octahedra, and  a faceface with one Br(1)Cs6 octahedra. The corner-sharing octahedral tilt angles range from 35-46°. is represented by the CIF file [CIF]
data_Cs3HgBr5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.386
_cell_length_b   11.313
_cell_length_c   14.209
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1508.739
_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  0.919  0.250  0.050  1.0
  Cs  Cs1  1  0.419  0.250  0.450  1.0
  Cs  Cs2  1  0.081  0.750  0.950  1.0
  Cs  Cs3  1  0.581  0.750  0.550  1.0
  Cs  Cs4  1  0.917  0.019  0.332  1.0
  Cs  Cs5  1  0.417  0.481  0.168  1.0
  Cs  Cs6  1  0.083  0.519  0.668  1.0
  Cs  Cs7  1  0.583  0.981  0.832  1.0
  Cs  Cs8  1  0.083  0.981  0.668  1.0
  Cs  Cs9  1  0.583  0.519  0.832  1.0
  Cs  Cs10  1  0.917  0.481  0.332  1.0
  Cs  Cs11  1  0.417  0.019  0.168  1.0
  Hg  Hg12  1  0.802  0.250  0.613  1.0
  Hg  Hg13  1  0.302  0.250  0.887  1.0
  Hg  Hg14  1  0.198  0.750  0.387  1.0
  Hg  Hg15  1  0.698  0.750  0.113  1.0
  Br  Br16  1  0.671  0.250  0.262  1.0
  Br  Br17  1  0.171  0.250  0.238  1.0
  Br  Br18  1  0.329  0.750  0.738  1.0
  Br  Br19  1  0.829  0.750  0.762  1.0
  Br  Br20  1  0.687  0.048  0.565  1.0
  Br  Br21  1  0.187  0.452  0.935  1.0
  Br  Br22  1  0.313  0.548  0.435  1.0
  Br  Br23  1  0.813  0.952  0.065  1.0
  Br  Br24  1  0.313  0.952  0.435  1.0
  Br  Br25  1  0.813  0.548  0.065  1.0
  Br  Br26  1  0.687  0.452  0.565  1.0
  Br  Br27  1  0.187  0.048  0.935  1.0
  Br  Br28  1  0.542  0.250  0.991  1.0
  Br  Br29  1  0.042  0.250  0.509  1.0
  Br  Br30  1  0.458  0.750  0.009  1.0
  Br  Br31  1  0.958  0.750  0.491  1.0
  Br  Br32  1  0.877  0.250  0.792  1.0
  Br  Br33  1  0.377  0.250  0.708  1.0
  Br  Br34  1  0.123  0.750  0.208  1.0
  Br  Br35  1  0.623  0.750  0.292  1.0
[/CIF]
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