data_[Na2Ca16Mg4]
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
  Mg  1.3100  1.5000  0.8600
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [17.5361]
_cell_length_b [5.9004]
_cell_length_c [9.1397]
_cell_angle_alpha [90.0000]
_cell_angle_beta [118.7051]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na(Ca4Mg)2]
_chemical_formula_sum '[Na2 Ca16 Mg4]'
_cell_volume [829.4684]
_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  0.0000  1.0
  Ca  Ca1  4  0.0532  0.0000  0.7253  1.0
  Ca  Ca2  4  0.1064  0.5000  0.4667  1.0
  Ca  Ca3  4  0.1484  0.0000  0.2110  1.0
  Ca  Ca4  4  0.1834  0.5000  0.9386  1.0
  Mg  Mg5  4  0.2208  0.0000  0.6333  1.0
]