data_[Pm6Mg8Hg8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Pm  1.1300  1.8500  1.1100
  Mg  1.3100  1.5000  0.8600
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [4.5324]
_cell_length_b [7.8779]
_cell_length_c [15.5558]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [Pm3(MgHg)4]
_chemical_formula_sum '[Pm6 Mg8 Hg8]'
_cell_volume [555.4276]
_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
[
  Pm  Pm0  4  0.0000  0.0000  0.1175  1
  Pm  Pm1  2  0.0000  0.5000  0.0000  1
  Mg  Mg2  8  0.0000  0.1928  0.6738  1
  Hg  Hg3  4  0.0000  0.2999  0.5000  1
  Hg  Hg4  4  0.0000  0.5000  0.2244  1
]