data_FeCu2B
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.56
_cell_length_b   2.56
_cell_length_c   6.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeCu2B
_chemical_formula_sum   'Fe1 Cu2 B1'
_cell_volume   40.58
_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
  Fe  Fe3  1  0.28  0.28  0.48  1.0
  Cu  Cu1  1  0.28  0.28  0.95  1.0
  Cu  Cu2  1  0.0  0.0  0.63  1.0
  B  B0  1  0.0  0.0  0.39  1.0

data_FeCu2B
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.62
_cell_length_b   3.62
_cell_length_c   6.18
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   FeCu2B
_chemical_formula_sum   'Fe2 Cu4 B2'
_cell_volume   81.16
_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
  Fe  Fe0  2  0.28  0.0  0.48  1.0
  Cu  Cu1  2  0.0  0.0  0.63  1.0
  Cu  Cu2  2  0.28  0.0  0.95  1.0
  B  B3  2  0.0  0.0  0.39  1.0

Fe Cu Cu B
Fe Cu Cu B 0 3 o o o 0 1 o o o 0 2 o o o 1 2 o o o 1 2 o + o 1 2 + o o 1 3 o o + 1 1 + o o 1 1 o + o 2 3 o o o 
FeCu2B crystallizes in the monoclinic Cm space group. Fe(1) is bonded in a 1-coordinate geometry to one Cu(2) and one B(1) atom. The Fe(1)-Cu(2) bond length is 1.41 Å. The Fe(1)-B(1) bond length is 1.16 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 8-coordinate geometry to three equivalent Cu(2), four equivalent Cu(1), and one B(1) atom. There is one shorter (2.22 Å) and two longer (2.79 Å) Cu(1)-Cu(2) bond lengths. All Cu(1)-Cu(1) bond lengths are 2.56 Å. The Cu(1)-B(1) bond length is 2.87 Å. In the second Cu site, Cu(2) is bonded in a 2-coordinate geometry to one Fe(1), three equivalent Cu(1), and one B(1) atom. The Cu(2)-B(1) bond length is 1.52 Å. B(1) is bonded in a 1-coordinate geometry to one Fe(1), one Cu(1), and one Cu(2) atom.