The crystal structure described by Ni3Nb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(1) atoms to form NbNi12 cuboctahedra that share corners with four equivalent Nb(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, edges with eight equivalent Nb(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(1)Nb4Ni8 cuboctahedra, faces with four equivalent Nb(1)Ni12 cuboctahedra, faces with six equivalent Ni(2)Nb4Ni8 cuboctahedra, and faces with eight equivalent Ni(1)Nb4Ni8 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Nb(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form NiNb4Ni8 cuboctahedra that share corners with twelve equivalent Ni(1)Nb4Ni8 cuboctahedra, edges with eight equivalent Nb(1)Ni12 cuboctahedra, edges with eight equivalent Ni(1)Nb4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, faces with four equivalent Nb(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Nb4Ni8 cuboctahedra, and faces with ten equivalent Ni(1)Nb4Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to four equivalent Nb(1) and eight equivalent Ni(1) atoms to form distorted NiNb4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Nb4Ni8 cuboctahedra, corners with eight equivalent Nb(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, edges with sixteen equivalent Ni(1)Nb4Ni8 cuboctahedra, faces with four equivalent Ni(2)Nb4Ni8 cuboctahedra, faces with six equivalent Nb(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(1)Nb4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_NbNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.617
_cell_length_b   3.617
_cell_length_c   4.515
_cell_angle_alpha   113.612
_cell_angle_beta   113.612
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   48.670
_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
  Nb  Nb0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.750  0.250  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.250  0.750  0.500  1.0
[/CIF]
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The crystal structure described by Ni3Nb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Nb(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(1) atoms to form NbNi12 cuboctahedra that share corners with four equivalent Nb(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, edges with eight equivalent Nb(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(1)Nb4Ni8 cuboctahedra, faces with four equivalent Nb(1)Ni12 cuboctahedra, faces with six equivalent Ni(2)Nb4Ni8 cuboctahedra, and faces with eight equivalent Ni(1)Nb4Ni8 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Nb(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form NiNb4Ni8 cuboctahedra that share corners with twelve equivalent Ni(1)Nb4Ni8 cuboctahedra, edges with eight equivalent Nb(1)Ni12 cuboctahedra, edges with eight equivalent Ni(1)Nb4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, faces with four equivalent Nb(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Nb4Ni8 cuboctahedra, and faces with ten equivalent Ni(1)Nb4Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to four equivalent Nb(1) and eight equivalent Ni(1) atoms to form distorted NiNb4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Nb4Ni8 cuboctahedra, corners with eight equivalent Nb(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Nb4Ni8 cuboctahedra, edges with sixteen equivalent Ni(1)Nb4Ni8 cuboctahedra, faces with four equivalent Ni(2)Nb4Ni8 cuboctahedra, faces with six equivalent Nb(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(1)Nb4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_NbNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.617
_cell_length_b   3.617
_cell_length_c   4.515
_cell_angle_alpha   113.612
_cell_angle_beta   113.612
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   48.670
_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
  Nb  Nb0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.750  0.250  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.250  0.750  0.500  1.0
[/CIF]
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