The compound described by HgCr2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(1), two equivalent S(4), and three equivalent S(2) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. In the second Cr site, Cr(2) is bonded to one S(4), two equivalent S(1), and three equivalent S(3) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. Hg(1) is bonded in a 7-coordinate geometry to one S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(1) atom to form distorted SCr3Hg trigonal pyramids that share corners with six equivalent S(3)Cr3Hg2 trigonal bipyramids, corners with two equivalent S(1)Cr3Hg trigonal pyramids, and  an edgeedge with one S(3)Cr3Hg2 trigonal bipyramid. In the second S site, S(2) is bonded in a 3-coordinate geometry to three equivalent Cr(1) and two equivalent Hg(1) atoms. In the third S site, S(3) is bonded to three equivalent Cr(2) and two equivalent Hg(1) atoms to form distorted SCr3Hg2 trigonal bipyramids that share corners with six equivalent S(1)Cr3Hg trigonal pyramids, edges with four equivalent S(3)Cr3Hg2 trigonal bipyramids, and  an edgeedge with one S(1)Cr3Hg trigonal pyramid. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to one Cr(2), two equivalent Cr(1), and two equivalent Hg(1) atoms. is represented by the CIF file [CIF]
data_Cr2HgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.524
_cell_length_b   11.205
_cell_length_c   12.854
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   507.513
_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
  Cr  Cr0  1  0.250  0.054  0.113  1.0
  Cr  Cr1  1  0.750  0.946  0.887  1.0
  Cr  Cr2  1  0.750  0.446  0.613  1.0
  Cr  Cr3  1  0.250  0.554  0.387  1.0
  Cr  Cr4  1  0.250  0.088  0.594  1.0
  Cr  Cr5  1  0.750  0.912  0.406  1.0
  Cr  Cr6  1  0.750  0.412  0.094  1.0
  Cr  Cr7  1  0.250  0.588  0.906  1.0
  Hg  Hg8  1  0.250  0.241  0.320  1.0
  Hg  Hg9  1  0.750  0.759  0.680  1.0
  Hg  Hg10  1  0.750  0.259  0.820  1.0
  Hg  Hg11  1  0.250  0.741  0.180  1.0
  S  S12  1  0.750  0.048  0.713  1.0
  S  S13  1  0.250  0.952  0.287  1.0
  S  S14  1  0.250  0.452  0.213  1.0
  S  S15  1  0.750  0.548  0.787  1.0
  S  S16  1  0.250  0.082  0.932  1.0
  S  S17  1  0.750  0.918  0.068  1.0
  S  S18  1  0.750  0.418  0.432  1.0
  S  S19  1  0.250  0.582  0.568  1.0
  S  S20  1  0.750  0.113  0.464  1.0
  S  S21  1  0.250  0.887  0.536  1.0
  S  S22  1  0.250  0.387  0.964  1.0
  S  S23  1  0.750  0.613  0.036  1.0
  S  S24  1  0.750  0.199  0.148  1.0
  S  S25  1  0.250  0.801  0.852  1.0
  S  S26  1  0.250  0.301  0.648  1.0
  S  S27  1  0.750  0.699  0.352  1.0
[/CIF]
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The compound described by HgCr2S4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(1), two equivalent S(4), and three equivalent S(2) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. In the second Cr site, Cr(2) is bonded to one S(4), two equivalent S(1), and three equivalent S(3) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 49-54°. Hg(1) is bonded in a 7-coordinate geometry to one S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(1) atom to form distorted SCr3Hg trigonal pyramids that share corners with six equivalent S(3)Cr3Hg2 trigonal bipyramids, corners with two equivalent S(1)Cr3Hg trigonal pyramids, and  an edgeedge with one S(3)Cr3Hg2 trigonal bipyramid. In the second S site, S(2) is bonded in a 3-coordinate geometry to three equivalent Cr(1) and two equivalent Hg(1) atoms. In the third S site, S(3) is bonded to three equivalent Cr(2) and two equivalent Hg(1) atoms to form distorted SCr3Hg2 trigonal bipyramids that share corners with six equivalent S(1)Cr3Hg trigonal pyramids, edges with four equivalent S(3)Cr3Hg2 trigonal bipyramids, and  an edgeedge with one S(1)Cr3Hg trigonal pyramid. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to one Cr(2), two equivalent Cr(1), and two equivalent Hg(1) atoms. is represented by the CIF file [CIF]
data_Cr2HgS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.524
_cell_length_b   11.205
_cell_length_c   12.854
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   507.513
_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
  Cr  Cr0  1  0.250  0.054  0.113  1.0
  Cr  Cr1  1  0.750  0.946  0.887  1.0
  Cr  Cr2  1  0.750  0.446  0.613  1.0
  Cr  Cr3  1  0.250  0.554  0.387  1.0
  Cr  Cr4  1  0.250  0.088  0.594  1.0
  Cr  Cr5  1  0.750  0.912  0.406  1.0
  Cr  Cr6  1  0.750  0.412  0.094  1.0
  Cr  Cr7  1  0.250  0.588  0.906  1.0
  Hg  Hg8  1  0.250  0.241  0.320  1.0
  Hg  Hg9  1  0.750  0.759  0.680  1.0
  Hg  Hg10  1  0.750  0.259  0.820  1.0
  Hg  Hg11  1  0.250  0.741  0.180  1.0
  S  S12  1  0.750  0.048  0.713  1.0
  S  S13  1  0.250  0.952  0.287  1.0
  S  S14  1  0.250  0.452  0.213  1.0
  S  S15  1  0.750  0.548  0.787  1.0
  S  S16  1  0.250  0.082  0.932  1.0
  S  S17  1  0.750  0.918  0.068  1.0
  S  S18  1  0.750  0.418  0.432  1.0
  S  S19  1  0.250  0.582  0.568  1.0
  S  S20  1  0.750  0.113  0.464  1.0
  S  S21  1  0.250  0.887  0.536  1.0
  S  S22  1  0.250  0.387  0.964  1.0
  S  S23  1  0.750  0.613  0.036  1.0
  S  S24  1  0.750  0.199  0.148  1.0
  S  S25  1  0.250  0.801  0.852  1.0
  S  S26  1  0.250  0.301  0.648  1.0
  S  S27  1  0.750  0.699  0.352  1.0
[/CIF]
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