data_HfCu2Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.5
_cell_length_b   3.5
_cell_length_c   5.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfCu2Sb
_chemical_formula_sum   'Hf1 Cu2 Sb1'
_cell_volume   70.79
_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
  Hf  Hf2  1  0.0  0.0  0.89  1.0
  Cu  Cu0  1  0.75  0.75  0.54  1.0
  Cu  Cu1  1  0.75  0.75  0.24  1.0
  Sb  Sb3  1  0.0  0.0  0.0  1.0

data_HfCu2Sb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.95
_cell_length_b   4.95
_cell_length_c   5.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   HfCu2Sb
_chemical_formula_sum   'Hf2 Cu4 Sb2'
_cell_volume   141.57
_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
  Hf  Hf0  2  0.0  0.0  0.89  1.0
  Cu  Cu1  2  0.25  0.5  0.24  1.0
  Cu  Cu2  2  0.25  0.5  0.54  1.0
  Sb  Sb3  2  0.0  0.0  0.0  1.0

Hf Cu Cu Sb
HfCu2Sb crystallizes in the monoclinic Cm space group. Hf(1) is bonded in a single-bond geometry to one Cu(1) and one Sb(1) atom. The Hf(1)-Cu(1) bond length is 2.37 Å. The Hf(1)-Sb(1) bond length is 0.62 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 2-coordinate geometry to one Hf(1) and one Cu(2) atom. The Cu(1)-Cu(2) bond length is 1.75 Å. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one Cu(1) and three equivalent Sb(1) atoms. There is one shorter (1.87 Å) and two longer (3.10 Å) Cu(2)-Sb(1) bond lengths. Sb(1) is bonded in a distorted single-bond geometry to one Hf(1) and three equivalent Cu(2) atoms.