data_FeCu2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.48
_cell_length_b   2.48
_cell_length_c   12.15
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeCu2
_chemical_formula_sum   'Fe2 Cu4'
_cell_volume   64.71
_cell_formula_units_Z   2
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
  Fe  Fe4  1  0.24  0.72  0.11  1.0
  Fe  Fe5  1  0.0  0.43  0.04  1.0
  Cu  Cu0  1  0.24  0.72  0.01  1.0
  Cu  Cu1  1  0.24  0.72  0.06  1.0
  Cu  Cu2  1  0.0  0.43  0.09  1.0
  Cu  Cu3  1  0.0  0.43  0.14  1.0

data_FeCu2
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.48
_cell_length_b   2.48
_cell_length_c   12.15
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   FeCu2
_chemical_formula_sum   'Fe2 Cu4'
_cell_volume   64.71
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Fe  Fe0  2  0.12  0.64  0.04  1.0
  Cu  Cu1  2  0.12  0.64  0.94  1.0
  Cu  Cu2  2  0.12  0.64  0.99  1.0

Fe Fe Cu Cu Cu Cu
Fe Fe Cu Cu Cu Cu 0 4 o o o 0 5 o o o 0 3 o o o 1 2 o o o 1 3 o o o 1 4 o o o 2 3 o o o 3 4 o o o 4 5 o o o 
CuFeCu crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one CuFeCu cluster. Fe(1) is bonded in a 3-coordinate geometry to one Cu(1) and two equivalent Cu(2) atoms. The Fe(1)-Cu(1) bond length is 0.72 Å. There is one shorter (0.61 Å) and one longer (0.72 Å) Fe(1)-Cu(2) bond length. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 2-coordinate geometry to one Fe(1) and one Cu(2) atom. The Cu(1)-Cu(2) bond length is 0.61 Å. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to two equivalent Fe(1), one Cu(1), and one Cu(2) atom. The Cu(2)-Cu(2) bond length is 0.72 Å.