data_FeNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.3
_cell_length_b   8.3
_cell_length_c   8.3
_cell_angle_alpha   17.32
_cell_angle_beta   17.32
_cell_angle_gamma   17.32
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeNi3
_chemical_formula_sum   'Fe1 Ni3'
_cell_volume   44.19
_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  Fe0  1  0.0  0.0  0.0  1.0
  Ni  Ni1  1  0.0  0.0  0.14  1.0
  Ni  Ni2  1  0.0  0.0  0.26  1.0
  Ni  Ni3  1  0.0  0.0  0.38  1.0

data_FeNi3
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.33
_cell_length_b   2.5
_cell_length_c   8.3
_cell_angle_alpha   90.0
_cell_angle_beta   100.01
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   FeNi3
_chemical_formula_sum   'Fe2 Ni6'
_cell_volume   88.38
_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  0.0  0.0  0.0  1.0
  Ni  Ni1  2  0.0  0.0  0.62  1.0
  Ni  Ni2  2  0.0  0.0  0.74  1.0
  Ni  Ni3  2  0.0  0.0  0.86  1.0

Fe Ni Ni Ni
Fe Ni Ni Ni 0 1 o o o 1 2 o o o 2 3 o o o 
Ni3Fe is Cyanogen Chloride-derived structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Ni3Fe clusters. Fe(1) is bonded in a single-bond geometry to one Ni(1) atom. The Fe(1)-Ni(1) bond length is 1.13 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to one Fe(1) and one Ni(2) atom. The Ni(1)-Ni(2) bond length is 1.01 Å. In the second Ni site, Ni(2) is bonded in a linear geometry to one Ni(1) and one Ni(3) atom. The Ni(2)-Ni(3) bond length is 1.01 Å. In the third Ni site, Ni(3) is bonded in a single-bond geometry to one Ni(2) atom.