data_[Ca20Hg8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [C2/c]
_cell_length_a [17.5267]
_cell_length_b [6.9931]
_cell_length_c [8.0492]
_cell_angle_alpha [90.0000]
_cell_angle_beta [97.8363]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [15]
_chemical_formula_structural [Ca5Hg2]
_chemical_formula_sum '[Ca20 Hg8]'
_cell_volume [977.3459]
_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  8  0.0906  0.1155  0.4250  1.0
  Ca  Ca1  8  0.2205  0.4130  0.8106  1.0
  Ca  Ca2  4  0.0000  0.4123  0.7500  1.0
  Hg  Hg3  8  0.1100  0.2987  0.0789  1.0
]