data_Sr2MgTl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.09
_cell_length_b   4.09
_cell_length_c   8.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr2MgTl
_chemical_formula_sum   'Sr2 Mg1 Tl1'
_cell_volume   141.94
_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
  Sr  Sr1  1  0.04  0.04  0.19  1.0
  Sr  Sr2  1  0.04  0.04  0.3  1.0
  Mg  Mg0  1  0.0  0.0  0.0  1.0
  Tl  Tl3  1  0.0  0.0  0.25  1.0

data_Sr2MgTl
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.78
_cell_length_b   5.78
_cell_length_c   8.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Sr2MgTl
_chemical_formula_sum   'Sr4 Mg2 Tl2'
_cell_volume   283.88
_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
  Sr  Sr0  2  0.04  0.0  0.19  1.0
  Sr  Sr1  2  0.04  0.0  0.3  1.0
  Mg  Mg2  2  0.0  0.0  0.0  1.0
  Tl  Tl3  2  0.0  0.0  0.25  1.0

Sr Sr Mg Tl
Sr2MgTl crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Sr2MgTl clusters. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted single-bond geometry to one Mg(1) and one Tl(1) atom. The Sr(1)-Mg(1) bond length is 1.65 Å. The Sr(1)-Tl(1) bond length is 0.53 Å. In the second Sr site, Sr(2) is bonded in a single-bond geometry to one Tl(1) atom. The Sr(2)-Tl(1) bond length is 0.53 Å. Mg(1) is bonded in a single-bond geometry to one Sr(1) atom. Tl(1) is bonded in a bent 120 degrees geometry to one Sr(1) and one Sr(2) atom.