The crystal structure described by K6HgSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted KSe4 tetrahedra that share corners with two equivalent Hg(1)Se4 tetrahedra, corners with eight equivalent K(1)Se4 tetrahedra, and  an edgeedge with one Hg(1)Se4 tetrahedra. In the second K site, K(2) is bonded in a 3-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. Hg(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted HgSe4 tetrahedra that share corners with six equivalent K(1)Se4 tetrahedra and edges with three equivalent K(1)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Hg(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Hg(1) atom. is represented by the CIF card [CIF]
data_K6HgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.413
_cell_length_b   10.413
_cell_length_c   7.951
_cell_angle_alpha   89.999
_cell_angle_beta   90.002
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   746.619
_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
  K  K0  1  0.149  0.299  0.206  1.0
  K  K1  1  0.149  0.851  0.206  1.0
  K  K2  1  0.701  0.851  0.206  1.0
  K  K3  1  0.851  0.701  0.706  1.0
  K  K4  1  0.851  0.149  0.706  1.0
  K  K5  1  0.299  0.149  0.706  1.0
  K  K6  1  0.526  0.053  0.378  1.0
  K  K7  1  0.526  0.474  0.378  1.0
  K  K8  1  0.947  0.474  0.378  1.0
  K  K9  1  0.474  0.947  0.878  1.0
  K  K10  1  0.474  0.526  0.878  1.0
  K  K11  1  0.053  0.526  0.878  1.0
  Hg  Hg12  1  0.333  0.667  0.501  1.0
  Hg  Hg13  1  0.667  0.333  0.001  1.0
  Se  Se14  1  0.333  0.667  0.155  1.0
  Se  Se15  1  0.667  0.333  0.655  1.0
  Se  Se16  1  0.811  0.621  0.105  1.0
  Se  Se17  1  0.811  0.189  0.105  1.0
  Se  Se18  1  0.379  0.189  0.105  1.0
  Se  Se19  1  0.189  0.379  0.605  1.0
  Se  Se20  1  0.189  0.811  0.605  1.0
  Se  Se21  1  0.621  0.811  0.605  1.0
[/CIF]
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The crystal structure described by K6HgSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted KSe4 tetrahedra that share corners with two equivalent Hg(1)Se4 tetrahedra, corners with eight equivalent K(1)Se4 tetrahedra, and  an edgeedge with one Hg(1)Se4 tetrahedra. In the second K site, K(2) is bonded in a 3-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. Hg(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form distorted HgSe4 tetrahedra that share corners with six equivalent K(1)Se4 tetrahedra and edges with three equivalent K(1)Se4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Hg(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Hg(1) atom. is represented by the CIF card [CIF]
data_K6HgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.413
_cell_length_b   10.413
_cell_length_c   7.951
_cell_angle_alpha   89.999
_cell_angle_beta   90.002
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   746.619
_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
  K  K0  1  0.149  0.299  0.206  1.0
  K  K1  1  0.149  0.851  0.206  1.0
  K  K2  1  0.701  0.851  0.206  1.0
  K  K3  1  0.851  0.701  0.706  1.0
  K  K4  1  0.851  0.149  0.706  1.0
  K  K5  1  0.299  0.149  0.706  1.0
  K  K6  1  0.526  0.053  0.378  1.0
  K  K7  1  0.526  0.474  0.378  1.0
  K  K8  1  0.947  0.474  0.378  1.0
  K  K9  1  0.474  0.947  0.878  1.0
  K  K10  1  0.474  0.526  0.878  1.0
  K  K11  1  0.053  0.526  0.878  1.0
  Hg  Hg12  1  0.333  0.667  0.501  1.0
  Hg  Hg13  1  0.667  0.333  0.001  1.0
  Se  Se14  1  0.333  0.667  0.155  1.0
  Se  Se15  1  0.667  0.333  0.655  1.0
  Se  Se16  1  0.811  0.621  0.105  1.0
  Se  Se17  1  0.811  0.189  0.105  1.0
  Se  Se18  1  0.379  0.189  0.105  1.0
  Se  Se19  1  0.189  0.379  0.605  1.0
  Se  Se20  1  0.189  0.811  0.605  1.0
  Se  Se21  1  0.621  0.811  0.605  1.0
[/CIF]
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