The material described by Ho2Ni7 crystallizes in the trigonal R-3m space group. There are five inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the second Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2), three equivalent Ni(3), six equivalent Ni(4), and six equivalent Ni(5) atoms. In the third Ho site, Ho(2) is bonded in a 12-coordinate geometry to three equivalent Ni(1) and nine equivalent Ni(5) atoms. In the fourth Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the fifth Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four equivalent Ni(4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra, faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Ho4Ni8 cuboctahedra. In the second Ni site, Ni(1) is bonded to six equivalent Ho(2) and six equivalent Ni(5) atoms to form NiHo6Ni6 cuboctahedra that share corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with six equivalent Ni(1)Ho6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(5)Ho5Ni7 cuboctahedra. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ho(1), three equivalent Ni(4), and three equivalent Ni(5) atoms. In the fourth Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra; faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra; and faces with eight Ni(4,4)Ho4Ni8 cuboctahedra. In the fifth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ho(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the sixth Ni site, Ni(4) is bonded to four equivalent Ho(1), two equivalent Ni(2), two equivalent Ni(3), and four equivalent Ni(4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra, faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Ho4Ni8 cuboctahedra. In the seventh Ni site, Ni(5) is bonded to two equivalent Ho(1), three equivalent Ho(2), one Ni(1), one Ni(2), one Ni(3), and four equivalent Ni(5) atoms to form distorted NiHo5Ni7 cuboctahedra that share corners with two equivalent Ni(1)Ho6Ni6 cuboctahedra; corners with six Ni(4,4)Ho4Ni8 cuboctahedra; corners with nine equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with four equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with four equivalent Ni(5)Ho5Ni7 cuboctahedra;  a faceface with one Ni(4)Ho4Ni8 cuboctahedra; faces with three equivalent Ni(1)Ho6Ni6 cuboctahedra; and faces with ten equivalent Ni(5)Ho5Ni7 cuboctahedra. In the eighth Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra; faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra; and faces with eight Ni(4,4)Ho4Ni8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2Ni7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.924
_cell_length_b   4.924
_cell_length_c   12.334
_cell_angle_alpha   78.487
_cell_angle_beta   78.487
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   251.971
_cell_formula_units_Z   2
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  0.948  0.948  0.155  1.0
  Ho  Ho1  1  0.052  0.052  0.845  1.0
  Ho  Ho2  1  0.852  0.852  0.444  1.0
  Ho  Ho3  1  0.148  0.148  0.556  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.722  0.722  0.834  1.0
  Ni  Ni6  1  0.278  0.278  0.166  1.0
  Ni  Ni7  1  0.611  0.611  0.166  1.0
  Ni  Ni8  1  0.389  0.389  0.834  1.0
  Ni  Ni9  1  0.000  0.500  0.000  1.0
  Ni  Ni10  1  0.500  0.000  0.000  1.0
  Ni  Ni11  1  0.500  0.500  0.000  1.0
  Ni  Ni12  1  0.389  0.389  0.330  1.0
  Ni  Ni13  1  0.891  0.389  0.330  1.0
  Ni  Ni14  1  0.389  0.891  0.330  1.0
  Ni  Ni15  1  0.611  0.611  0.670  1.0
  Ni  Ni16  1  0.109  0.611  0.670  1.0
  Ni  Ni17  1  0.611  0.109  0.670  1.0
[/CIF]
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The material described by Ho2Ni7 crystallizes in the trigonal R-3m space group. There are five inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the second Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2), three equivalent Ni(3), six equivalent Ni(4), and six equivalent Ni(5) atoms. In the third Ho site, Ho(2) is bonded in a 12-coordinate geometry to three equivalent Ni(1) and nine equivalent Ni(5) atoms. In the fourth Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the fifth Ho site, Ho(1) is bonded in a 18-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four equivalent Ni(4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra, faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Ho4Ni8 cuboctahedra. In the second Ni site, Ni(1) is bonded to six equivalent Ho(2) and six equivalent Ni(5) atoms to form NiHo6Ni6 cuboctahedra that share corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with six equivalent Ni(1)Ho6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(5)Ho5Ni7 cuboctahedra. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ho(1), three equivalent Ni(4), and three equivalent Ni(5) atoms. In the fourth Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra; faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra; and faces with eight Ni(4,4)Ho4Ni8 cuboctahedra. In the fifth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ho(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the sixth Ni site, Ni(4) is bonded to four equivalent Ho(1), two equivalent Ni(2), two equivalent Ni(3), and four equivalent Ni(4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra, edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra, faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Ho4Ni8 cuboctahedra. In the seventh Ni site, Ni(5) is bonded to two equivalent Ho(1), three equivalent Ho(2), one Ni(1), one Ni(2), one Ni(3), and four equivalent Ni(5) atoms to form distorted NiHo5Ni7 cuboctahedra that share corners with two equivalent Ni(1)Ho6Ni6 cuboctahedra; corners with six Ni(4,4)Ho4Ni8 cuboctahedra; corners with nine equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with four equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with four equivalent Ni(5)Ho5Ni7 cuboctahedra;  a faceface with one Ni(4)Ho4Ni8 cuboctahedra; faces with three equivalent Ni(1)Ho6Ni6 cuboctahedra; and faces with ten equivalent Ni(5)Ho5Ni7 cuboctahedra. In the eighth Ni site, Ni(4) is bonded to four Ho(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiHo4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Ho4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Ho5Ni7 cuboctahedra; edges with two equivalent Ni(4)Ho4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Ho5Ni7 cuboctahedra; faces with two equivalent Ni(5)Ho5Ni7 cuboctahedra; and faces with eight Ni(4,4)Ho4Ni8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2Ni7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.924
_cell_length_b   4.924
_cell_length_c   12.334
_cell_angle_alpha   78.487
_cell_angle_beta   78.487
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   251.971
_cell_formula_units_Z   2
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  0.948  0.948  0.155  1.0
  Ho  Ho1  1  0.052  0.052  0.845  1.0
  Ho  Ho2  1  0.852  0.852  0.444  1.0
  Ho  Ho3  1  0.148  0.148  0.556  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.722  0.722  0.834  1.0
  Ni  Ni6  1  0.278  0.278  0.166  1.0
  Ni  Ni7  1  0.611  0.611  0.166  1.0
  Ni  Ni8  1  0.389  0.389  0.834  1.0
  Ni  Ni9  1  0.000  0.500  0.000  1.0
  Ni  Ni10  1  0.500  0.000  0.000  1.0
  Ni  Ni11  1  0.500  0.500  0.000  1.0
  Ni  Ni12  1  0.389  0.389  0.330  1.0
  Ni  Ni13  1  0.891  0.389  0.330  1.0
  Ni  Ni14  1  0.389  0.891  0.330  1.0
  Ni  Ni15  1  0.611  0.611  0.670  1.0
  Ni  Ni16  1  0.109  0.611  0.670  1.0
  Ni  Ni17  1  0.611  0.109  0.670  1.0
[/CIF]
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