data_Mg2TlSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.22
_cell_length_b   3.22
_cell_length_c   8.25
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   93.24
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2TlSi
_chemical_formula_sum   'Mg2 Tl1 Si1'
_cell_volume   85.49
_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  0.21  0.0  0.47  1.0
  Mg  Mg1  1  0.21  0.0  0.78  1.0
  Tl  Tl3  1  0.0  0.0  0.13  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0

data_Mg2TlSi
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.22
_cell_length_b   3.22
_cell_length_c   8.25
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   93.24
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2TlSi
_chemical_formula_sum   'Mg2 Tl1 Si1'
_cell_volume   85.49
_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  0.21  0.0  0.47  1.0
  Mg  Mg1  1  0.21  0.0  0.78  1.0
  Tl  Tl2  1  0.0  0.0  0.13  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

Mg Mg Tl Si
Mg2TlSi crystallizes in the triclinic P1 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one Mg(2), four equivalent Mg(1), and one Tl(1) atom to form a mixture of distorted corner and edge-sharing MgMg5Tl octahedra. The corner-sharing octahedra are not tilted. The Mg(1)-Mg(2) bond length is 2.53 Å. All Mg(1)-Mg(1) bond lengths are 3.22 Å. The Mg(1)-Tl(1) bond length is 2.94 Å. In the second Mg site, Mg(2) is bonded in a single-bond geometry to one Mg(1) and one Si(1) atom. The Mg(2)-Si(1) bond length is 1.94 Å. Tl(1) is bonded in a single-bond geometry to one Mg(1) and one Si(1) atom. The Tl(1)-Si(1) bond length is 1.04 Å. Si(1) is bonded in a distorted bent 150 degrees geometry to one Mg(2) and one Tl(1) atom.