data_[Ca6Si6O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R-3c]
_cell_length_a [5.0651]
_cell_length_b [5.0651]
_cell_length_c [12.3670]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [167]
_chemical_formula_structural [CaSiO3]
_chemical_formula_sum '[Ca6 Si6 O18]'
_cell_volume [274.7714]
_cell_formula_units_Z [6]
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  6  0.0000  0.0000  0.2500  1
  Si  Si1  6  0.0000  0.0000  0.0000  1
  O  O2  18  -0.0000  0.4666  0.2500  1
]