The structure described by Fe3Ni is alpha La-derived structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Fe(2), six equivalent Fe(1), and three equivalent Ni(1) atoms to form FeFe9Ni3 cuboctahedra that share corners with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Fe(2)Fe12 cuboctahedra, faces with six equivalent Fe(1)Fe9Ni3 cuboctahedra, and faces with six equivalent Ni(1)Fe6Ni6 cuboctahedra. In the second Fe site, Fe(2) is bonded to six equivalent Fe(1) and six equivalent Fe(2) atoms to form FeFe12 cuboctahedra that share corners with six equivalent Fe(2)Fe12 cuboctahedra, corners with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Fe(2)Fe12 cuboctahedra, and faces with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra. Ni(1) is bonded to six equivalent Fe(1) and six equivalent Ni(1) atoms to form NiFe6Ni6 cuboctahedra that share corners with six equivalent Fe(2)Fe12 cuboctahedra, corners with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Ni(1)Fe6Ni6 cuboctahedra, and faces with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra. is represented by the CIF card [CIF]
data_Fe3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.417
_cell_length_b   8.417
_cell_length_c   8.417
_cell_angle_alpha   17.105
_cell_angle_beta   17.105
_cell_angle_gamma   17.105
_symmetry_Int_Tables_number   1
_cell_volume   45.001
_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  0.250  0.250  0.250  1.0
  Fe  Fe1  1  0.500  0.500  0.500  1.0
  Fe  Fe2  1  0.750  0.750  0.750  1.0
  Ni  Ni3  1  0.000  0.000  0.000  1.0
[/CIF]
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The structure described by Fe3Ni is alpha La-derived structured and crystallizes in the trigonal R-3m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Fe(2), six equivalent Fe(1), and three equivalent Ni(1) atoms to form FeFe9Ni3 cuboctahedra that share corners with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Fe(2)Fe12 cuboctahedra, faces with six equivalent Fe(1)Fe9Ni3 cuboctahedra, and faces with six equivalent Ni(1)Fe6Ni6 cuboctahedra. In the second Fe site, Fe(2) is bonded to six equivalent Fe(1) and six equivalent Fe(2) atoms to form FeFe12 cuboctahedra that share corners with six equivalent Fe(2)Fe12 cuboctahedra, corners with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Fe(2)Fe12 cuboctahedra, and faces with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra. Ni(1) is bonded to six equivalent Fe(1) and six equivalent Ni(1) atoms to form NiFe6Ni6 cuboctahedra that share corners with six equivalent Fe(2)Fe12 cuboctahedra, corners with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with six equivalent Fe(2)Fe12 cuboctahedra, edges with six equivalent Ni(1)Fe6Ni6 cuboctahedra, edges with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra, faces with six equivalent Ni(1)Fe6Ni6 cuboctahedra, and faces with twelve equivalent Fe(1)Fe9Ni3 cuboctahedra. is represented by the CIF card [CIF]
data_Fe3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.417
_cell_length_b   8.417
_cell_length_c   8.417
_cell_angle_alpha   17.105
_cell_angle_beta   17.105
_cell_angle_gamma   17.105
_symmetry_Int_Tables_number   1
_cell_volume   45.001
_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  0.250  0.250  0.250  1.0
  Fe  Fe1  1  0.500  0.500  0.500  1.0
  Fe  Fe2  1  0.750  0.750  0.750  1.0
  Ni  Ni3  1  0.000  0.000  0.000  1.0
[/CIF]
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