data_Na2HfCu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.04
_cell_length_b   11.04
_cell_length_c   11.04
_cell_angle_alpha   15.77
_cell_angle_beta   15.77
_cell_angle_gamma   15.77
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2HfCu
_chemical_formula_sum   'Na2 Hf1 Cu1'
_cell_volume   86.56
_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
  Na  Na2  1  0.0  0.0  0.47  1.0
  Na  Na3  1  0.0  0.0  0.23  1.0
  Hf  Hf1  1  0.0  0.0  0.35  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0

data_Na2HfCu
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.24
_cell_length_b   3.03
_cell_length_c   11.04
_cell_angle_alpha   90.0
_cell_angle_beta   99.11
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Na2HfCu
_chemical_formula_sum   'Na4 Hf2 Cu2'
_cell_volume   173.12
_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
  Na  Na0  2  0.0  0.0  0.53  1.0
  Na  Na1  2  0.0  0.0  0.77  1.0
  Hf  Hf2  2  0.0  0.0  0.65  1.0
  Cu  Cu3  2  0.0  0.0  0.0  1.0

Na Na Hf Cu
Na Na Hf Cu 0 2 o o o 1 2 o o o 1 3 o o o 3 3 o + - 3 3 + - o 3 3 + o - 
Na2HfCu is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Na2HfCu clusters. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a single-bond geometry to one Hf(1) atom. The Na(1)-Hf(1) bond length is 1.34 Å. In the second Na site, Na(2) is bonded in a distorted linear geometry to one Hf(1) and one Cu(1) atom. The Na(2)-Hf(1) bond length is 1.34 Å. The Na(2)-Cu(1) bond length is 2.53 Å. Hf(1) is bonded in a linear geometry to one Na(1) and one Na(2) atom. Cu(1) is bonded in a single-bond geometry to one Na(2) atom.