data_[La6Mg3Si3O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  La  1.1000  1.9500  1.1720
  Mg  1.3100  1.5000  0.8600
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [5.4496]
_cell_length_b [5.4496]
_cell_length_c [13.2184]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [La2MgSiO6]
_chemical_formula_sum '[La6 Mg3 Si3 O18]'
_cell_volume [339.9634]
_cell_formula_units_Z [3]
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
[
  La  La0  6  0.0000  0.0000  0.2495  1.0
  Mg  Mg1  3  -0.0000  0.0000  0.5000  1.0
  Si  Si2  3  0.0000  0.0000  0.0000  1.0
  O  O3  18  0.0229  0.5574  0.7454  1.0
]