data_TlCuAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.38
_cell_length_b   3.9
_cell_length_c   5.59
_cell_angle_alpha   90.0
_cell_angle_beta   105.51
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlCuAs2
_chemical_formula_sum   'Tl1 Cu1 As2'
_cell_volume   92.14
_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  0.44  0.0  0.69  1.0
  Cu  Cu2  1  0.0  0.0  0.0  1.0
  As  As0  1  0.16  0.95  0.78  1.0
  As  As1  1  0.73  0.95  0.6  1.0

data_TlCuAs2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.9
_cell_length_b   4.38
_cell_length_c   5.59
_cell_angle_alpha   105.51
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlCuAs2
_chemical_formula_sum   'Tl1 Cu1 As2'
_cell_volume   92.14
_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  0.0  0.56  0.31  1.0
  Cu  Cu1  1  0.0  0.0  0.0  1.0
  As  As2  1  0.05  0.27  0.4  1.0
  As  As3  1  0.05  0.84  0.22  1.0

Tl Cu As As
CuTlAs2 is Indium-like structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one CuTlAs2 cluster. Cu(1) is bonded in a distorted single-bond geometry to one As(1) atom. The Cu(1)-As(1) bond length is 1.57 Å. Tl(1) is bonded in a distorted linear geometry to one As(1) and one As(2) atom. The Tl(1)-As(1) bond length is 1.48 Å. The Tl(1)-As(2) bond length is 1.48 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a distorted bent 150 degrees geometry to one Cu(1) and one Tl(1) atom. In the second As site, As(2) is bonded in a single-bond geometry to one Tl(1) atom.