data_[Ca20Sn4Hg8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Sn  1.9600  1.4500  0.8300
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [I4/mcm]
_cell_length_a [8.1961]
_cell_length_b [8.1961]
_cell_length_c [14.9188]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [140]
_chemical_formula_structural [Ca5SnHg2]
_chemical_formula_sum '[Ca20 Sn4 Hg8]'
_cell_volume [1002.1816]
_cell_formula_units_Z [4]
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
[
  Ca  Ca0  16  0.1695  0.3305  0.1470  1
  Ca  Ca1  4  0.0000  0.0000  0.0000  1
  Sn  Sn2  4  0.0000  0.0000  0.2500  1
  Hg  Hg3  8  0.1293  0.3707  0.5000  1
]