data_MgTlAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   4.18
_cell_angle_alpha   101.4
_cell_angle_beta   101.4
_cell_angle_gamma   105.52
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgTlAs2
_chemical_formula_sum   'Mg1 Tl1 As2'
_cell_volume   91.93
_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
  Mg  Mg2  1  0.0  0.0  0.0  1.0
  Tl  Tl3  1  0.97  0.0  0.0  1.0
  As  As0  1  0.81  0.96  0.97  1.0
  As  As1  1  0.81  0.04  0.97  1.0

data_MgTlAs2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.18
_cell_length_b   4.92
_cell_length_c   4.92
_cell_angle_alpha   105.52
_cell_angle_beta   101.4
_cell_angle_gamma   101.4
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgTlAs2
_chemical_formula_sum   'Mg1 Tl1 As2'
_cell_volume   91.93
_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
  Mg  Mg0  1  0.0  0.0  0.0  1.0
  Tl  Tl1  1  0.0  0.97  0.0  1.0
  As  As2  1  0.97  0.81  0.04  1.0
  As  As3  1  0.97  0.81  0.96  1.0

Mg Tl As As
Mg Tl As As 0 1 - o o 2 3 o + o 
MgTlAs2 is Indium-like structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one MgTlAs2 cluster. Mg(1) is bonded in a single-bond geometry to one Tl(1) atom. The Mg(1)-Tl(1) bond length is 0.12 Å. Tl(1) is bonded in a 2-coordinate geometry to one Mg(1), one As(1), and one As(2) atom. The Tl(1)-As(1) bond length is 0.78 Å. The Tl(1)-As(2) bond length is 0.91 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in an L-shaped geometry to one Tl(1) and one As(2) atom. The As(1)-As(2) bond length is 0.43 Å. In the second As site, As(2) is bonded in a 2-coordinate geometry to one Tl(1) and one As(1) atom.