The crystal structure described by MgTl3 is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Tl(1) and eight equivalent Tl(2) atoms to form MgTl12 cuboctahedra that share corners with four equivalent Mg(1)Tl12 cuboctahedra, corners with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with eight equivalent Mg(1)Tl12 cuboctahedra, edges with sixteen equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Mg(1)Tl12 cuboctahedra, faces with six equivalent Tl(1)Mg4Tl8 cuboctahedra, and faces with eight equivalent Tl(2)Mg4Tl8 cuboctahedra. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to four equivalent Mg(1) and eight equivalent Tl(2) atoms to form distorted TlMg4Tl8 cuboctahedra that share corners with four equivalent Tl(1)Mg4Tl8 cuboctahedra, corners with eight equivalent Mg(1)Tl12 cuboctahedra, edges with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with sixteen equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Tl(1)Mg4Tl8 cuboctahedra, faces with six equivalent Mg(1)Tl12 cuboctahedra, and faces with eight equivalent Tl(2)Mg4Tl8 cuboctahedra. In the second Tl site, Tl(2) is bonded to four equivalent Mg(1), four equivalent Tl(1), and four equivalent Tl(2) atoms to form TlMg4Tl8 cuboctahedra that share corners with twelve equivalent Tl(2)Mg4Tl8 cuboctahedra, edges with eight equivalent Mg(1)Tl12 cuboctahedra, edges with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with eight equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Mg(1)Tl12 cuboctahedra, faces with four equivalent Tl(1)Mg4Tl8 cuboctahedra, and faces with ten equivalent Tl(2)Mg4Tl8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.010
_cell_length_b   6.010
_cell_length_c   6.010
_cell_angle_alpha   134.477
_cell_angle_beta   134.477
_cell_angle_gamma   66.344
_symmetry_Int_Tables_number   1
_cell_volume   108.805
_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  0.000  0.000  0.000  1.0
  Tl  Tl1  1  0.500  0.500  0.000  1.0
  Tl  Tl2  1  0.750  0.250  0.500  1.0
  Tl  Tl3  1  0.250  0.750  0.500  1.0
[/CIF]
.
The crystal structure described by MgTl3 is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Tl(1) and eight equivalent Tl(2) atoms to form MgTl12 cuboctahedra that share corners with four equivalent Mg(1)Tl12 cuboctahedra, corners with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with eight equivalent Mg(1)Tl12 cuboctahedra, edges with sixteen equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Mg(1)Tl12 cuboctahedra, faces with six equivalent Tl(1)Mg4Tl8 cuboctahedra, and faces with eight equivalent Tl(2)Mg4Tl8 cuboctahedra. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded to four equivalent Mg(1) and eight equivalent Tl(2) atoms to form distorted TlMg4Tl8 cuboctahedra that share corners with four equivalent Tl(1)Mg4Tl8 cuboctahedra, corners with eight equivalent Mg(1)Tl12 cuboctahedra, edges with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with sixteen equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Tl(1)Mg4Tl8 cuboctahedra, faces with six equivalent Mg(1)Tl12 cuboctahedra, and faces with eight equivalent Tl(2)Mg4Tl8 cuboctahedra. In the second Tl site, Tl(2) is bonded to four equivalent Mg(1), four equivalent Tl(1), and four equivalent Tl(2) atoms to form TlMg4Tl8 cuboctahedra that share corners with twelve equivalent Tl(2)Mg4Tl8 cuboctahedra, edges with eight equivalent Mg(1)Tl12 cuboctahedra, edges with eight equivalent Tl(1)Mg4Tl8 cuboctahedra, edges with eight equivalent Tl(2)Mg4Tl8 cuboctahedra, faces with four equivalent Mg(1)Tl12 cuboctahedra, faces with four equivalent Tl(1)Mg4Tl8 cuboctahedra, and faces with ten equivalent Tl(2)Mg4Tl8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.010
_cell_length_b   6.010
_cell_length_c   6.010
_cell_angle_alpha   134.477
_cell_angle_beta   134.477
_cell_angle_gamma   66.344
_symmetry_Int_Tables_number   1
_cell_volume   108.805
_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  0.000  0.000  0.000  1.0
  Tl  Tl1  1  0.500  0.500  0.000  1.0
  Tl  Tl2  1  0.750  0.250  0.500  1.0
  Tl  Tl3  1  0.250  0.750  0.500  1.0
[/CIF]
.