The crystal structure described by Mg5Tl2 crystallizes in the triclinic P-1 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the third Mg site, Mg(3) is bonded to one Mg(2), one Mg(5), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Tl(1), and two equivalent Tl(2) atoms to form a mixture of distorted corner and face-sharing MgMg8Tl4 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a 4-coordinate geometry to two equivalent Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the fifth Mg site, Mg(5) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Mg(5) atoms. In the second Tl site, Tl(2) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Mg(5) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Tl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.214
_cell_length_b   7.333
_cell_length_c   8.504
_cell_angle_alpha   115.587
_cell_angle_beta   111.354
_cell_angle_gamma   89.967
_symmetry_Int_Tables_number   1
_cell_volume   319.778
_cell_formula_units_Z   2
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  0.411  0.075  0.825  1.0
  Mg  Mg1  1  0.484  0.733  0.466  1.0
  Mg  Mg2  1  0.251  0.501  0.002  1.0
  Mg  Mg3  1  0.089  0.250  0.176  1.0
  Mg  Mg4  1  0.589  0.925  0.175  1.0
  Mg  Mg5  1  0.516  0.267  0.534  1.0
  Mg  Mg6  1  0.019  0.267  0.537  1.0
  Mg  Mg7  1  0.981  0.733  0.463  1.0
  Mg  Mg8  1  0.911  0.750  0.824  1.0
  Mg  Mg9  1  0.749  0.499  0.998  1.0
  Tl  Tl10  1  0.623  0.354  0.244  1.0
  Tl  Tl11  1  0.878  0.110  0.757  1.0
  Tl  Tl12  1  0.122  0.890  0.243  1.0
  Tl  Tl13  1  0.377  0.646  0.756  1.0
[/CIF]
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The crystal structure described by Mg5Tl2 crystallizes in the triclinic P-1 space group. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the third Mg site, Mg(3) is bonded to one Mg(2), one Mg(5), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Tl(1), and two equivalent Tl(2) atoms to form a mixture of distorted corner and face-sharing MgMg8Tl4 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a 4-coordinate geometry to two equivalent Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. In the fifth Mg site, Mg(5) is bonded in a 4-coordinate geometry to one Mg(3), two equivalent Tl(1), and two equivalent Tl(2) atoms. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Mg(5) atoms. In the second Tl site, Tl(2) is bonded in a distorted q6 geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Mg(5) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg5Tl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.214
_cell_length_b   7.333
_cell_length_c   8.504
_cell_angle_alpha   115.587
_cell_angle_beta   111.354
_cell_angle_gamma   89.967
_symmetry_Int_Tables_number   1
_cell_volume   319.778
_cell_formula_units_Z   2
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  0.411  0.075  0.825  1.0
  Mg  Mg1  1  0.484  0.733  0.466  1.0
  Mg  Mg2  1  0.251  0.501  0.002  1.0
  Mg  Mg3  1  0.089  0.250  0.176  1.0
  Mg  Mg4  1  0.589  0.925  0.175  1.0
  Mg  Mg5  1  0.516  0.267  0.534  1.0
  Mg  Mg6  1  0.019  0.267  0.537  1.0
  Mg  Mg7  1  0.981  0.733  0.463  1.0
  Mg  Mg8  1  0.911  0.750  0.824  1.0
  Mg  Mg9  1  0.749  0.499  0.998  1.0
  Tl  Tl10  1  0.623  0.354  0.244  1.0
  Tl  Tl11  1  0.878  0.110  0.757  1.0
  Tl  Tl12  1  0.122  0.890  0.243  1.0
  Tl  Tl13  1  0.377  0.646  0.756  1.0
[/CIF]
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