data_TlHgAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.1
_cell_length_b   5.1
_cell_length_c   5.1
_cell_angle_alpha   119.66
_cell_angle_beta   119.66
_cell_angle_gamma   90.6
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlHgAs2
_chemical_formula_sum   'Tl1 Hg1 As2'
_cell_volume   94.4
_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
  Tl  Tl3  1  0.0  0.56  0.79  1.0
  Hg  Hg2  1  0.0  0.0  0.59  1.0
  As  As0  1  0.0  0.0  0.0  1.0
  As  As1  1  0.56  0.0  0.79  1.0

data_TlHgAs2
_symmetry_space_group_name_H-M   P1
_cell_length_a   5.1
_cell_length_b   5.1
_cell_length_c   5.1
_cell_angle_alpha   90.6
_cell_angle_beta   119.66
_cell_angle_gamma   119.66
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlHgAs2
_chemical_formula_sum   'Tl1 Hg1 As2'
_cell_volume   94.4
_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
  Tl  Tl0  1  0.79  0.0  0.56  1.0
  Hg  Hg1  1  0.59  0.0  0.0  1.0
  As  As2  1  0.0  0.0  0.0  1.0
  As  As3  1  0.79  0.56  0.0  1.0

Tl Hg As As
HgTlAs2 crystallizes in the triclinic P1 space group. Hg(1) is bonded in a 3-coordinate geometry to one Tl(1), one As(2), and two equivalent As(1) atoms. The Hg(1)-Tl(1) bond length is 2.53 Å. The Hg(1)-As(2) bond length is 2.53 Å. There is one shorter (2.10 Å) and one longer (3.01 Å) Hg(1)-As(1) bond length. Tl(1) is bonded in a 2-coordinate geometry to one Hg(1) and one As(1) atom. The Tl(1)-As(1) bond length is 1.93 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 4-coordinate geometry to two equivalent Hg(1), one Tl(1), and one As(2) atom. The As(1)-As(2) bond length is 1.93 Å. In the second As site, As(2) is bonded in a distorted linear geometry to one Hg(1) and one As(1) atom.