data_BaHf2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.68
_cell_length_b   8.68
_cell_length_c   8.68
_cell_angle_alpha   158.2
_cell_angle_beta   158.2
_cell_angle_gamma   31.02
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaHf2
_chemical_formula_sum   'Ba1 Hf2'
_cell_volume   90.06
_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  0.0  0.0  1.0
  Hf  Hf1  1  0.0  0.0  0.57  1.0
  Hf  Hf2  1  0.0  0.0  0.16  1.0

data_BaHf2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.64
_cell_length_b   4.64
_cell_length_c   8.68
_cell_angle_alpha   90.0
_cell_angle_beta   105.51
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   BaHf2
_chemical_formula_sum   'Ba2 Hf4'
_cell_volume   180.11
_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
  Ba  Ba0  2  0.0  0.0  0.0  1.0
  Hf  Hf1  2  0.0  0.0  0.43  1.0
  Hf  Hf2  2  0.0  0.0  0.84  1.0

Ba Hf Hf
BaHf2 crystallizes in the monoclinic Cm space group. Ba(1) is bonded in a single-bond geometry to one Hf(1) and one Hf(2) atom. The Ba(1)-Hf(1) bond length is 3.74 Å. The Ba(1)-Hf(2) bond length is 1.36 Å. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 6-coordinate geometry to one Ba(1), one Hf(2), and four equivalent Hf(1) atoms. The Hf(1)-Hf(2) bond length is 3.58 Å. All Hf(1)-Hf(1) bond lengths are 3.28 Å. In the second Hf site, Hf(2) is bonded in a single-bond geometry to one Ba(1) and one Hf(1) atom.