data_[Mg16Cu2Hg4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Cu  1.9000  1.3500  0.8200
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [15.9974]
_cell_length_b [4.7428]
_cell_length_c [6.5986]
_cell_angle_alpha [90.0000]
_cell_angle_beta [112.5498]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Mg8CuHg2]
_chemical_formula_sum '[Mg16 Cu2 Hg4]'
_cell_volume [462.3776]
_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  4  0.0169  0.0000  0.7849  1
  Mg  Mg1  4  0.1006  0.5000  0.4241  1
  Mg  Mg2  4  0.1539  0.5000  0.9297  1
  Mg  Mg3  4  0.1904  0.0000  0.2562  1
  Cu  Cu4  2  0.0000  0.5000  0.0000  1
  Hg  Hg5  4  0.1798  0.0000  0.6850  1
]