data_[Ca4Nb4O14]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Nb  1.6000  1.4500  0.8200
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [6.8659]
_cell_length_b [9.7805]
_cell_length_c [5.5421]
_cell_angle_alpha [90.0000]
_cell_angle_beta [101.1263]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Ca2Nb2O7]
_chemical_formula_sum '[Ca4 Nb4 O14]'
_cell_volume [365.1714]
_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  0.0000  0.3125  0.0000  1.0
  Nb  Nb1  4  0.2470  0.5000  0.6076  1.0
  O  O2  8  0.2288  0.1592  0.2052  1.0
  O  O3  4  0.0680  0.5000  0.2902  1.0
  O  O4  2  0.0000  0.0000  0.5000  1.0
]