data_[Ca4P6O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  P  2.1900  1.0000  0.5500
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P6_3/m]
_cell_length_a [6.7959]
_cell_length_b [6.7959]
_cell_length_c [9.6544]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [176]
_chemical_formula_structural [Ca2(PO3)3]
_chemical_formula_sum '[Ca4 P6 O18]'
_cell_volume [386.1388]
_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
[
  Ca  Ca0  4  0.3333  0.6667  0.0280  1
  P  P1  6  0.0125  0.7498  0.7500  1
  O  O2  12  0.0318  0.6501  0.6140  1
  O  O3  6  0.0130  0.7921  0.2500  1
]