The material described by Cr3Ni is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to eight equivalent Cr(2) and four equivalent Ni(1) atoms to form CrCr8Ni4 cuboctahedra that share corners with four equivalent Cr(1)Cr8Ni4 cuboctahedra, corners with eight equivalent Ni(1)Cr12 cuboctahedra, edges with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with sixteen equivalent Cr(2)Cr8Ni4 cuboctahedra, faces with four equivalent Cr(1)Cr8Ni4 cuboctahedra, faces with six equivalent Ni(1)Cr12 cuboctahedra, and faces with eight equivalent Cr(2)Cr8Ni4 cuboctahedra. In the second Cr site, Cr(2) is bonded to four equivalent Cr(1), four equivalent Cr(2), and four equivalent Ni(1) atoms to form CrCr8Ni4 cuboctahedra that share corners with twelve equivalent Cr(2)Cr8Ni4 cuboctahedra, edges with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with eight equivalent Cr(2)Cr8Ni4 cuboctahedra, edges with eight equivalent Ni(1)Cr12 cuboctahedra, faces with four equivalent Cr(1)Cr8Ni4 cuboctahedra, faces with four equivalent Ni(1)Cr12 cuboctahedra, and faces with ten equivalent Cr(2)Cr8Ni4 cuboctahedra. Ni(1) is bonded to four equivalent Cr(1) and eight equivalent Cr(2) atoms to form NiCr12 cuboctahedra that share corners with four equivalent Ni(1)Cr12 cuboctahedra, corners with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with eight equivalent Ni(1)Cr12 cuboctahedra, edges with sixteen equivalent Cr(2)Cr8Ni4 cuboctahedra, faces with four equivalent Ni(1)Cr12 cuboctahedra, faces with six equivalent Cr(1)Cr8Ni4 cuboctahedra, and faces with eight equivalent Cr(2)Cr8Ni4 cuboctahedra. is represented by the CIF card [CIF]
data_Cr3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.386
_cell_length_b   4.386
_cell_length_c   4.386
_cell_angle_alpha   131.687
_cell_angle_beta   131.687
_cell_angle_gamma   70.724
_symmetry_Int_Tables_number   1
_cell_volume   46.097
_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
  Cr  Cr0  1  0.500  0.500  0.000  1.0
  Cr  Cr1  1  0.750  0.250  0.500  1.0
  Cr  Cr2  1  0.250  0.750  0.500  1.0
  Ni  Ni3  1  0.000  0.000  0.000  1.0
[/CIF]
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The material described by Cr3Ni is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to eight equivalent Cr(2) and four equivalent Ni(1) atoms to form CrCr8Ni4 cuboctahedra that share corners with four equivalent Cr(1)Cr8Ni4 cuboctahedra, corners with eight equivalent Ni(1)Cr12 cuboctahedra, edges with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with sixteen equivalent Cr(2)Cr8Ni4 cuboctahedra, faces with four equivalent Cr(1)Cr8Ni4 cuboctahedra, faces with six equivalent Ni(1)Cr12 cuboctahedra, and faces with eight equivalent Cr(2)Cr8Ni4 cuboctahedra. In the second Cr site, Cr(2) is bonded to four equivalent Cr(1), four equivalent Cr(2), and four equivalent Ni(1) atoms to form CrCr8Ni4 cuboctahedra that share corners with twelve equivalent Cr(2)Cr8Ni4 cuboctahedra, edges with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with eight equivalent Cr(2)Cr8Ni4 cuboctahedra, edges with eight equivalent Ni(1)Cr12 cuboctahedra, faces with four equivalent Cr(1)Cr8Ni4 cuboctahedra, faces with four equivalent Ni(1)Cr12 cuboctahedra, and faces with ten equivalent Cr(2)Cr8Ni4 cuboctahedra. Ni(1) is bonded to four equivalent Cr(1) and eight equivalent Cr(2) atoms to form NiCr12 cuboctahedra that share corners with four equivalent Ni(1)Cr12 cuboctahedra, corners with eight equivalent Cr(1)Cr8Ni4 cuboctahedra, edges with eight equivalent Ni(1)Cr12 cuboctahedra, edges with sixteen equivalent Cr(2)Cr8Ni4 cuboctahedra, faces with four equivalent Ni(1)Cr12 cuboctahedra, faces with six equivalent Cr(1)Cr8Ni4 cuboctahedra, and faces with eight equivalent Cr(2)Cr8Ni4 cuboctahedra. is represented by the CIF card [CIF]
data_Cr3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.386
_cell_length_b   4.386
_cell_length_c   4.386
_cell_angle_alpha   131.687
_cell_angle_beta   131.687
_cell_angle_gamma   70.724
_symmetry_Int_Tables_number   1
_cell_volume   46.097
_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
  Cr  Cr0  1  0.500  0.500  0.000  1.0
  Cr  Cr1  1  0.750  0.250  0.500  1.0
  Cr  Cr2  1  0.250  0.750  0.500  1.0
  Ni  Ni3  1  0.000  0.000  0.000  1.0
[/CIF]
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