The compound described by Hg2SnSe4 crystallizes in the tetragonal I-4 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to four equivalent Se(1) atoms to form HgSe4 tetrahedra that share corners with four equivalent Hg(2)Se4 tetrahedra and corners with four equivalent Sn(1)Se4 tetrahedra. In the second Hg site, Hg(2) is bonded to four equivalent Se(1) atoms to form HgSe4 tetrahedra that share corners with four equivalent Hg(1)Se4 tetrahedra and corners with four equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to four equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with four equivalent Hg(1)Se4 tetrahedra and corners with four equivalent Hg(2)Se4 tetrahedra. Se(1) is bonded in a trigonal non-coplanar geometry to one Hg(1), one Hg(2), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sn(HgSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.879
_cell_length_b   5.879
_cell_length_c   7.212
_cell_angle_alpha   114.052
_cell_angle_beta   114.052
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.696
_cell_formula_units_Z   1
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
  Sn  Sn0  1  0.250  0.750  0.500  1.0
  Hg  Hg1  1  0.500  0.500  0.000  1.0
  Hg  Hg2  1  0.750  0.250  0.500  1.0
  Se  Se3  1  0.905  0.346  0.230  1.0
  Se  Se4  1  0.116  0.095  0.770  1.0
  Se  Se5  1  0.654  0.675  0.770  1.0
  Se  Se6  1  0.325  0.884  0.230  1.0
[/CIF]
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The compound described by Hg2SnSe4 crystallizes in the tetragonal I-4 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to four equivalent Se(1) atoms to form HgSe4 tetrahedra that share corners with four equivalent Hg(2)Se4 tetrahedra and corners with four equivalent Sn(1)Se4 tetrahedra. In the second Hg site, Hg(2) is bonded to four equivalent Se(1) atoms to form HgSe4 tetrahedra that share corners with four equivalent Hg(1)Se4 tetrahedra and corners with four equivalent Sn(1)Se4 tetrahedra. Sn(1) is bonded to four equivalent Se(1) atoms to form SnSe4 tetrahedra that share corners with four equivalent Hg(1)Se4 tetrahedra and corners with four equivalent Hg(2)Se4 tetrahedra. Se(1) is bonded in a trigonal non-coplanar geometry to one Hg(1), one Hg(2), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sn(HgSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.879
_cell_length_b   5.879
_cell_length_c   7.212
_cell_angle_alpha   114.052
_cell_angle_beta   114.052
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.696
_cell_formula_units_Z   1
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
  Sn  Sn0  1  0.250  0.750  0.500  1.0
  Hg  Hg1  1  0.500  0.500  0.000  1.0
  Hg  Hg2  1  0.750  0.250  0.500  1.0
  Se  Se3  1  0.905  0.346  0.230  1.0
  Se  Se4  1  0.116  0.095  0.770  1.0
  Se  Se5  1  0.654  0.675  0.770  1.0
  Se  Se6  1  0.325  0.884  0.230  1.0
[/CIF]
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