data_KHf2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.45
_cell_length_b   6.45
_cell_length_c   6.45
_cell_angle_alpha   140.89
_cell_angle_beta   140.89
_cell_angle_gamma   56.51
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KHf2Mg
_chemical_formula_sum   'K1 Hf2 Mg1'
_cell_volume   105.68
_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
  K  K2  1  0.0  0.0  0.68  1.0
  Hf  Hf0  1  0.16  0.0  0.84  1.0
  Hf  Hf1  1  0.0  0.16  0.84  1.0
  Mg  Mg3  1  0.0  0.0  0.0  1.0

data_KHf2Mg
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.1
_cell_length_b   6.1
_cell_length_c   6.45
_cell_angle_alpha   90.0
_cell_angle_beta   118.25
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   KHf2Mg
_chemical_formula_sum   'K2 Hf4 Mg2'
_cell_volume   211.37
_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
  K  K0  2  0.0  0.0  0.32  1.0
  Hf  Hf1  4  0.08  0.08  0.32  1.0
  Mg  Mg2  2  0.0  0.0  0.0  1.0

K Hf Hf Mg
KMgHf2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two KMgHf2 clusters. K(1) is bonded in an L-shaped geometry to one Mg(1) and two equivalent Hf(1) atoms. The K(1)-Mg(1) bond length is 2.08 Å. Both K(1)-Hf(1) bond lengths are 0.69 Å. Mg(1) is bonded in a 3-coordinate geometry to one K(1) and two equivalent Hf(1) atoms. Both Mg(1)-Hf(1) bond lengths are 1.94 Å. Hf(1) is bonded in a single-bond geometry to one K(1) and one Mg(1) atom.