The crystal structure described by HoNi3 crystallizes in the trigonal R-3m space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 12-coordinate geometry to three equivalent Ni(2) and nine equivalent Ni(1) atoms. In the second Ho site, Ho(2) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(3) and twelve equivalent Ni(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Ho(2), three equivalent Ho(1), one Ni(2), two equivalent Ni(3), and four equivalent Ni(1) atoms to form distorted NiHo5Ni7 cuboctahedra that share corners with two equivalent Ni(2)Ho6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Ho5Ni7 cuboctahedra, edges with eight equivalent Ni(1)Ho5Ni7 cuboctahedra, faces with three equivalent Ni(2)Ho6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Ho5Ni7 cuboctahedra. In the second Ni site, Ni(2) is bonded to six equivalent Ho(1) and six equivalent Ni(1) atoms to form NiHo6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Ho5Ni7 cuboctahedra, edges with six equivalent Ni(2)Ho6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Ho5Ni7 cuboctahedra. In the third Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ho(2) and six equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_HoNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.482
_cell_length_b   8.482
_cell_length_c   8.482
_cell_angle_alpha   33.598
_cell_angle_beta   33.598
_cell_angle_gamma   33.598
_symmetry_Int_Tables_number   1
_cell_volume   166.470
_cell_formula_units_Z   3
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
  Ho  Ho0  1  0.861  0.861  0.861  1.0
  Ho  Ho1  1  0.139  0.139  0.139  1.0
  Ho  Ho2  1  0.000  0.000  0.000  1.0
  Ni  Ni3  1  0.418  0.418  0.920  1.0
  Ni  Ni4  1  0.920  0.418  0.418  1.0
  Ni  Ni5  1  0.418  0.920  0.418  1.0
  Ni  Ni6  1  0.500  0.500  0.500  1.0
  Ni  Ni7  1  0.333  0.333  0.333  1.0
  Ni  Ni8  1  0.667  0.667  0.667  1.0
  Ni  Ni9  1  0.080  0.582  0.582  1.0
  Ni  Ni10  1  0.582  0.582  0.080  1.0
  Ni  Ni11  1  0.582  0.080  0.582  1.0
[/CIF]
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The crystal structure described by HoNi3 crystallizes in the trigonal R-3m space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 12-coordinate geometry to three equivalent Ni(2) and nine equivalent Ni(1) atoms. In the second Ho site, Ho(2) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(3) and twelve equivalent Ni(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Ho(2), three equivalent Ho(1), one Ni(2), two equivalent Ni(3), and four equivalent Ni(1) atoms to form distorted NiHo5Ni7 cuboctahedra that share corners with two equivalent Ni(2)Ho6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Ho5Ni7 cuboctahedra, edges with eight equivalent Ni(1)Ho5Ni7 cuboctahedra, faces with three equivalent Ni(2)Ho6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Ho5Ni7 cuboctahedra. In the second Ni site, Ni(2) is bonded to six equivalent Ho(1) and six equivalent Ni(1) atoms to form NiHo6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Ho5Ni7 cuboctahedra, edges with six equivalent Ni(2)Ho6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Ho5Ni7 cuboctahedra. In the third Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ho(2) and six equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_HoNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.482
_cell_length_b   8.482
_cell_length_c   8.482
_cell_angle_alpha   33.598
_cell_angle_beta   33.598
_cell_angle_gamma   33.598
_symmetry_Int_Tables_number   1
_cell_volume   166.470
_cell_formula_units_Z   3
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
  Ho  Ho0  1  0.861  0.861  0.861  1.0
  Ho  Ho1  1  0.139  0.139  0.139  1.0
  Ho  Ho2  1  0.000  0.000  0.000  1.0
  Ni  Ni3  1  0.418  0.418  0.920  1.0
  Ni  Ni4  1  0.920  0.418  0.418  1.0
  Ni  Ni5  1  0.418  0.920  0.418  1.0
  Ni  Ni6  1  0.500  0.500  0.500  1.0
  Ni  Ni7  1  0.333  0.333  0.333  1.0
  Ni  Ni8  1  0.667  0.667  0.667  1.0
  Ni  Ni9  1  0.080  0.582  0.582  1.0
  Ni  Ni10  1  0.582  0.582  0.080  1.0
  Ni  Ni11  1  0.582  0.080  0.582  1.0
[/CIF]
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