data_HfTaCu2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.92
_cell_length_b   2.92
_cell_length_c   7.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   92.69
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfTaCu2
_chemical_formula_sum   'Hf1 Ta1 Cu2'
_cell_volume   63.79
_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  0.9  1.0
  Ta  Ta3  1  0.02  0.0  0.66  1.0
  Cu  Cu0  1  0.0  0.0  0.3  1.0
  Cu  Cu1  1  0.02  0.0  0.86  1.0

data_HfTaCu2
_symmetry_space_group_name_H-M   Cmm2
_cell_length_a   4.03
_cell_length_b   4.22
_cell_length_c   7.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   35
_chemical_formula_structural   HfTaCu2
_chemical_formula_sum   'Hf2 Ta2 Cu4'
_cell_volume   127.58
_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, y, z'
  4  'x, -y, z'
  5  'x+1/2, y+1/2, z'
  6  '-x+1/2, -y+1/2, z'
  7  '-x+1/2, y+1/2, z'
  8  '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  0.1  1.0
  Ta  Ta1  2  0.0  0.0  0.34  1.0
  Cu  Cu2  2  0.0  0.0  0.14  1.0
  Cu  Cu3  2  0.0  0.0  0.7  1.0

Hf Ta Cu Cu
HfTaCu2 crystallizes in the triclinic P1 space group. Hf(1) is bonded in a single-bond geometry to one Cu(1) and one Cu(2) atom. The Hf(1)-Cu(1) bond length is 3.04 Å. The Hf(1)-Cu(2) bond length is 0.26 Å. Ta(1) is bonded in a distorted single-bond geometry to one Cu(1) and one Cu(2) atom. The Ta(1)-Cu(1) bond length is 2.68 Å. The Ta(1)-Cu(2) bond length is 1.52 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Hf(1), one Ta(1), and four equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing CuHfTaCu4 octahedra. The corner-sharing octahedra are not tilted. All Cu(1)-Cu(1) bond lengths are 2.92 Å. In the second Cu site, Cu(2) is bonded in a distorted single-bond geometry to one Hf(1) and one Ta(1) atom.