data_Mg3Tl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.31
_cell_length_b   3.31
_cell_length_c   8.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg3Tl
_chemical_formula_sum   'Mg3 Tl1'
_cell_volume   96.38
_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  0.66  0.66  0.17  1.0
  Mg  Mg1  1  0.0  0.0  0.0  1.0
  Mg  Mg2  1  0.66  0.66  0.61  1.0
  Tl  Tl3  1  0.0  0.0  0.39  1.0

data_Mg3Tl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.68
_cell_length_b   4.68
_cell_length_c   8.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mg3Tl
_chemical_formula_sum   'Mg6 Tl2'
_cell_volume   192.76
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.0  1.0
  Mg  Mg1  2  0.16  0.5  0.17  1.0
  Mg  Mg2  2  0.16  0.5  0.61  1.0
  Tl  Tl3  2  0.0  0.0  0.39  1.0

Mg Mg Mg Tl
Mg3Tl crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Mg3Tl clusters. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 2-coordinate geometry to one Mg(2) and one Tl(1) atom. The Mg(1)-Mg(2) bond length is 2.19 Å. The Mg(1)-Tl(1) bond length is 2.53 Å. In the second Mg site, Mg(2) is bonded in a distorted single-bond geometry to one Mg(1) atom. In the third Mg site, Mg(3) is bonded in a distorted single-bond geometry to one Tl(1) atom. The Mg(3)-Tl(1) bond length is 2.53 Å. Tl(1) is bonded in a distorted water-like geometry to one Mg(1) and one Mg(3) atom.