data_Mg2TlZn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.31
_cell_length_b   3.31
_cell_length_c   8.2
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2TlZn
_chemical_formula_sum   'Mg2 Tl1 Zn1'
_cell_volume   90.06
_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  0.99  1.0
  Mg  Mg1  1  0.0  0.0  0.94  1.0
  Tl  Tl2  1  0.66  0.66  0.24  1.0
  Zn  Zn3  1  0.0  0.0  0.32  1.0

data_Mg2TlZn
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.69
_cell_length_b   4.69
_cell_length_c   8.2
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mg2TlZn
_chemical_formula_sum   'Mg4 Tl2 Zn2'
_cell_volume   180.11
_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  0.94  1.0
  Mg  Mg1  2  0.16  0.5  0.99  1.0
  Tl  Tl2  2  0.16  0.5  0.24  1.0
  Zn  Zn3  2  0.0  0.0  0.32  1.0

Mg Mg Tl Zn
Mg Mg Tl Zn 0 1 + + o 0 2 o o + 2 3 + + o 