data_SnHgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.08
_cell_length_b   4.36
_cell_length_c   5.57
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SnHgSe2
_chemical_formula_sum   'Sn1 Hg1 Se2'
_cell_volume   99.06
_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  Sn3  1  0.04  0.0  0.79  1.0
  Hg  Hg0  1  0.0  0.18  0.79  1.0
  Se  Se1  1  0.0  0.0  0.0  1.0
  Se  Se2  1  0.04  0.18  0.0  1.0

data_SnHgSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.08
_cell_length_b   4.36
_cell_length_c   5.57
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SnHgSe2
_chemical_formula_sum   'Sn1 Hg1 Se2'
_cell_volume   99.06
_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  0.04  0.0  0.79  1.0
  Hg  Hg1  1  0.0  0.18  0.79  1.0
  Se  Se2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.04  0.18  0.0  1.0

Sn Hg Se Se
Sn Hg Se Se 0 1 o o o 2 3 o o o 
HgSnSe2 is Indium-like structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one HgSnSe2 cluster. Hg(1) is bonded in an L-shaped geometry to one Sn(1) and one Se(2) atom. The Hg(1)-Sn(1) bond length is 0.80 Å. The Hg(1)-Se(2) bond length is 1.21 Å. Sn(1) is bonded in an L-shaped geometry to one Hg(1) and one Se(1) atom. The Sn(1)-Se(1) bond length is 1.21 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in an L-shaped geometry to one Sn(1) and one Se(2) atom. The Se(1)-Se(2) bond length is 0.80 Å. In the second Se site, Se(2) is bonded in an L-shaped geometry to one Hg(1) and one Se(1) atom.