data_BaTi2Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   7.1
_cell_angle_alpha   92.15
_cell_angle_beta   92.15
_cell_angle_gamma   36.49
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaTi2Nb
_chemical_formula_sum   'Ba1 Ti2 Nb1'
_cell_volume   102.13
_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
  Ba  Ba0  1  0.56  0.0  0.53  1.0
  Ti  Ti2  1  0.32  0.0  0.05  1.0
  Ti  Ti3  1  0.22  0.0  0.98  1.0
  Nb  Nb1  1  0.84  0.0  0.09  1.0

data_BaTi2Nb
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.08
_cell_length_b   4.92
_cell_length_c   7.1
_cell_angle_alpha   92.15
_cell_angle_beta   90.0
_cell_angle_gamma   108.24
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaTi2Nb
_chemical_formula_sum   'Ba1 Ti2 Nb1'
_cell_volume   102.13
_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
  Ba  Ba0  1  0.0  0.44  0.47  1.0
  Ti  Ti1  1  0.0  0.68  0.95  1.0
  Ti  Ti2  1  0.0  0.78  0.02  1.0
  Nb  Nb3  1  0.0  0.16  0.91  1.0

Ba Ti Ti Nb
BaTi2Nb crystallizes in the triclinic P1 space group. Ba(1) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Ti(1), one Ti(2), and one Nb(1) atom. Both Ba(1)-Ba(1) bond lengths are 3.08 Å. The Ba(1)-Ti(1) bond length is 3.56 Å. The Ba(1)-Ti(2) bond length is 3.66 Å. The Ba(1)-Nb(1) bond length is 3.46 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ti(2), and one Nb(1) atom. The Ti(1)-Ti(2) bond length is 0.70 Å. The Ti(1)-Nb(1) bond length is 2.57 Å. In the second Ti site, Ti(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ti(1), and one Nb(1) atom. The Ti(2)-Nb(1) bond length is 2.04 Å. Nb(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ti(1), and one Ti(2) atom.