data_MgBe2Tl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.09
_cell_length_b   4.09
_cell_length_c   3.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   91.76
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgBe2Tl
_chemical_formula_sum   'Mg1 Be2 Tl1'
_cell_volume   64.32
_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  Mg2  1  0.0  0.0  0.0  1.0
  Be  Be0  1  0.42  0.53  0.92  1.0
  Be  Be1  1  0.42  0.47  0.92  1.0
  Tl  Tl3  1  0.85  0.0  0.0  1.0

data_MgBe2Tl
_symmetry_space_group_name_H-M   Pm
_cell_length_a   3.85
_cell_length_b   4.09
_cell_length_c   4.09
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   MgBe2Tl
_chemical_formula_sum   'Mg1 Be2 Tl1'
_cell_volume   64.35
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '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  0.0  0.0  0.0  1.0
  Be  Be1  2  0.92  0.47  0.42  1.0
  Tl  Tl2  1  0.0  0.0  0.85  1.0

Mg Be Be Tl
Mg Be Be Tl 0 3 - o o 1 2 o o o 