data_Li2HfNb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.22
_cell_length_b   3.22
_cell_length_c   6.41
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2HfNb
_chemical_formula_sum   'Li2 Hf1 Nb1'
_cell_volume   66.36
_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
  Li  Li1  1  0.61  0.61  0.87  1.0
  Li  Li2  1  0.61  0.61  0.54  1.0
  Hf  Hf0  1  0.0  0.0  0.21  1.0
  Nb  Nb3  1  0.0  0.0  0.0  1.0

data_Li2HfNb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.55
_cell_length_b   4.55
_cell_length_c   6.41
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Li2HfNb
_chemical_formula_sum   'Li4 Hf2 Nb2'
_cell_volume   132.71
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Li  Li0  2  0.11  0.5  0.54  1.0
  Li  Li1  2  0.11  0.5  0.87  1.0
  Hf  Hf2  2  0.0  0.0  0.21  1.0
  Nb  Nb3  2  0.0  0.0  0.0  1.0

Li Li Hf Nb
Li Li Hf Nb 0 1 o o o 0 3 + + + 2 3 o o o 
Li2HfNb crystallizes in the monoclinic Cm space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one Li(2) and four equivalent Nb(1) atoms. The Li(1)-Li(2) bond length is 2.13 Å. There are a spread of Li(1)-Nb(1) bond distances ranging from 1.96-2.89 Å. In the second Li site, Li(2) is bonded in a 2-coordinate geometry to one Li(1) and one Hf(1) atom. The Li(2)-Hf(1) bond length is 2.79 Å. Hf(1) is bonded in a single-bond geometry to one Li(2) and one Nb(1) atom. The Hf(1)-Nb(1) bond length is 1.32 Å. Nb(1) is bonded in a 5-coordinate geometry to four equivalent Li(1) and one Hf(1) atom.