data_BaHf2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.57
_cell_length_b   5.57
_cell_length_c   5.57
_cell_angle_alpha   126.79
_cell_angle_beta   126.79
_cell_angle_gamma   78.59
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaHf2Mg
_chemical_formula_sum   'Ba1 Hf2 Mg1'
_cell_volume   107.55
_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  0.5  0.0  0.16  1.0
  Hf  Hf1  1  0.0  0.0  0.31  1.0
  Hf  Hf2  1  0.0  0.5  0.16  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0

data_BaHf2Mg
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.99
_cell_length_b   4.99
_cell_length_c   5.57
_cell_angle_alpha   116.6
_cell_angle_beta   116.6
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaHf2Mg
_chemical_formula_sum   'Ba1 Hf2 Mg1'
_cell_volume   107.55
_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  0.16  0.66  0.66  1.0
  Hf  Hf1  1  0.31  0.31  0.31  1.0
  Hf  Hf2  1  0.66  0.16  0.66  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0

Ba Hf Hf Mg
BaMgHf2 crystallizes in the triclinic P1 space group. Ba(1) is bonded in a distorted linear geometry to one Mg(1), one Hf(1), and two equivalent Hf(2) atoms. The Ba(1)-Mg(1) bond length is 2.35 Å. The Ba(1)-Hf(1) bond length is 2.39 Å. Both Ba(1)-Hf(2) bond lengths are 3.53 Å. Mg(1) is bonded in a 3-coordinate geometry to one Ba(1), one Hf(1), and one Hf(2) atom. The Mg(1)-Hf(1) bond length is 1.75 Å. The Mg(1)-Hf(2) bond length is 2.35 Å. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 2-coordinate geometry to one Ba(1), one Mg(1), and one Hf(2) atom. The Hf(1)-Hf(2) bond length is 2.39 Å. In the second Hf site, Hf(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Mg(1), and one Hf(1) atom.