data_[Na2Ca6Hg2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ca  1.0000  1.8000  1.1400
  Hg  2.0000  1.5000  1.2450
]
_symmetry_space_group_name_H-M [Pmmn]
_cell_length_a [5.0174]
_cell_length_b [9.5990]
_cell_length_c [7.3416]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [59]
_chemical_formula_structural [NaCa3Hg]
_chemical_formula_sum '[Na2 Ca6 Hg2]'
_cell_volume [353.5892]
_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
[
  Na  Na0  2  0.0000  0.5000  0.4368  1.0
  Ca  Ca1  4  0.0000  0.2001  0.8008  1.0
  Ca  Ca2  2  0.0000  0.0000  0.2450  1.0
  Hg  Hg3  2  0.0000  0.5000  0.0193  1.0
]