data_Na2TiNb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.15
_cell_length_b   5.15
_cell_length_c   6.7
_cell_angle_alpha   94.42
_cell_angle_beta   94.42
_cell_angle_gamma   30.78
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2TiNb
_chemical_formula_sum   'Na2 Ti1 Nb1'
_cell_volume   90.64
_cell_formula_units_Z   1
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  1  0.5  0.0  0.64  1.0
  Na  Na1  1  0.03  0.0  0.01  1.0
  Ti  Ti3  1  0.42  0.0  0.1  1.0
  Nb  Nb2  1  0.6  0.0  0.94  1.0

data_Na2TiNb
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.73
_cell_length_b   5.15
_cell_length_c   6.7
_cell_angle_alpha   94.42
_cell_angle_beta   90.0
_cell_angle_gamma   105.39
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2TiNb
_chemical_formula_sum   'Na2 Ti1 Nb1'
_cell_volume   90.64
_cell_formula_units_Z   1
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  1  0.0  0.5  0.36  1.0
  Na  Na1  1  0.0  0.97  0.99  1.0
  Ti  Ti2  1  0.0  0.58  0.9  1.0
  Nb  Nb3  1  0.0  0.4  0.06  1.0

Na Na Ti Nb
Na Na Ti Nb 0 3 o o o 1 3 - o - 1 2 o o o 2 3 o o - 