The compound described by Ni9S8 crystallizes in the orthorhombic C222 space group. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one S(2), one S(3), and three equivalent S(4) atoms to form distorted NiS5 square pyramids that share  a cornercorner with one Ni(2)S4 tetrahedra,  a cornercorner with one Ni(3)S4 tetrahedra,  a cornercorner with one Ni(4)S4 tetrahedra,  a cornercorner with one Ni(5)S4 tetrahedra, corners with two equivalent Ni(8)S4 tetrahedra, corners with three equivalent Ni(7)S4 tetrahedra, edges with three equivalent Ni(1)S5 square pyramids, and  an edgeedge with one Ni(8)S4 tetrahedra. In the second Ni site, Ni(2) is bonded to four equivalent S(3) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids and edges with two equivalent Ni(4)S4 tetrahedra. In the third Ni site, Ni(3) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted NiS4 tetrahedra that share corners with two equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(4)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, corners with two equivalent Ni(8)S4 tetrahedra, and  an edgeedge with one Ni(5)S4 tetrahedra. In the fourth Ni site, Ni(4) is bonded to two equivalent S(1) and two equivalent S(3) atoms to form distorted NiS4 tetrahedra that share corners with two equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, and  an edgeedge with one Ni(2)S4 tetrahedra. In the fifth Ni site, Ni(5) is bonded to four equivalent S(2) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids, edges with two equivalent Ni(3)S4 tetrahedra, and edges with two equivalent Ni(8)S4 tetrahedra. In the sixth Ni site, Ni(6) is bonded in a 5-coordinate geometry to one S(2), two equivalent S(1), and two equivalent S(3) atoms. In the seventh Ni site, Ni(7) is bonded to two equivalent S(1) and two equivalent S(4) atoms to form NiS4 tetrahedra that share corners with six equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(4)S4 tetrahedra, and corners with two equivalent Ni(8)S4 tetrahedra. In the eighth Ni site, Ni(8) is bonded to two equivalent S(2) and two equivalent S(4) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, edges with two equivalent Ni(1)S5 square pyramids, and  an edgeedge with one Ni(5)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Ni(3), one Ni(4), one Ni(7), and two equivalent Ni(6) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to one Ni(1), one Ni(3), one Ni(5), one Ni(6), and one Ni(8) atom. In the third S site, S(3) is bonded in a distorted pentagonal planar geometry to one Ni(1), one Ni(2), one Ni(4), and two equivalent Ni(6) atoms. In the fourth S site, S(4) is bonded to one Ni(7), one Ni(8), and three equivalent Ni(1) atoms to form a mixture of distorted corner, face, and edge-sharing SNi5 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni9S8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.201
_cell_length_b   7.201
_cell_length_c   9.314
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   79.432
_symmetry_Int_Tables_number   1
_cell_volume   474.785
_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
  Ni  Ni0  1  0.714  0.462  0.373  1.0
  Ni  Ni1  1  0.286  0.538  0.373  1.0
  Ni  Ni2  1  0.538  0.286  0.627  1.0
  Ni  Ni3  1  0.462  0.714  0.627  1.0
  Ni  Ni4  1  0.500  0.500  0.000  1.0
  Ni  Ni5  1  0.000  0.000  0.214  1.0
  Ni  Ni6  1  0.000  0.000  0.786  1.0
  Ni  Ni7  1  0.222  0.778  0.000  1.0
  Ni  Ni8  1  0.778  0.222  0.000  1.0
  Ni  Ni9  1  0.000  0.000  0.500  1.0
  Ni  Ni10  1  0.057  0.309  0.122  1.0
  Ni  Ni11  1  0.943  0.691  0.122  1.0
  Ni  Ni12  1  0.691  0.943  0.878  1.0
  Ni  Ni13  1  0.309  0.057  0.878  1.0
  Ni  Ni14  1  0.500  0.000  0.270  1.0
  Ni  Ni15  1  0.000  0.500  0.730  1.0
  Ni  Ni16  1  0.237  0.237  0.500  1.0
  Ni  Ni17  1  0.763  0.763  0.500  1.0
  S  S18  1  0.730  0.967  0.119  1.0
  S  S19  1  0.270  0.033  0.119  1.0
  S  S20  1  0.033  0.270  0.881  1.0
  S  S21  1  0.967  0.730  0.881  1.0
  S  S22  1  0.983  0.248  0.360  1.0
  S  S23  1  0.017  0.752  0.360  1.0
  S  S24  1  0.752  0.017  0.640  1.0
  S  S25  1  0.248  0.983  0.640  1.0
  S  S26  1  0.749  0.484  0.134  1.0
  S  S27  1  0.251  0.516  0.134  1.0
  S  S28  1  0.516  0.251  0.866  1.0
  S  S29  1  0.484  0.749  0.866  1.0
  S  S30  1  0.498  0.259  0.386  1.0
  S  S31  1  0.502  0.741  0.386  1.0
  S  S32  1  0.741  0.502  0.614  1.0
  S  S33  1  0.259  0.498  0.614  1.0
[/CIF]
.
The compound described by Ni9S8 crystallizes in the orthorhombic C222 space group. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one S(2), one S(3), and three equivalent S(4) atoms to form distorted NiS5 square pyramids that share  a cornercorner with one Ni(2)S4 tetrahedra,  a cornercorner with one Ni(3)S4 tetrahedra,  a cornercorner with one Ni(4)S4 tetrahedra,  a cornercorner with one Ni(5)S4 tetrahedra, corners with two equivalent Ni(8)S4 tetrahedra, corners with three equivalent Ni(7)S4 tetrahedra, edges with three equivalent Ni(1)S5 square pyramids, and  an edgeedge with one Ni(8)S4 tetrahedra. In the second Ni site, Ni(2) is bonded to four equivalent S(3) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids and edges with two equivalent Ni(4)S4 tetrahedra. In the third Ni site, Ni(3) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted NiS4 tetrahedra that share corners with two equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(4)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, corners with two equivalent Ni(8)S4 tetrahedra, and  an edgeedge with one Ni(5)S4 tetrahedra. In the fourth Ni site, Ni(4) is bonded to two equivalent S(1) and two equivalent S(3) atoms to form distorted NiS4 tetrahedra that share corners with two equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, and  an edgeedge with one Ni(2)S4 tetrahedra. In the fifth Ni site, Ni(5) is bonded to four equivalent S(2) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids, edges with two equivalent Ni(3)S4 tetrahedra, and edges with two equivalent Ni(8)S4 tetrahedra. In the sixth Ni site, Ni(6) is bonded in a 5-coordinate geometry to one S(2), two equivalent S(1), and two equivalent S(3) atoms. In the seventh Ni site, Ni(7) is bonded to two equivalent S(1) and two equivalent S(4) atoms to form NiS4 tetrahedra that share corners with six equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(4)S4 tetrahedra, and corners with two equivalent Ni(8)S4 tetrahedra. In the eighth Ni site, Ni(8) is bonded to two equivalent S(2) and two equivalent S(4) atoms to form NiS4 tetrahedra that share corners with four equivalent Ni(1)S5 square pyramids, corners with two equivalent Ni(3)S4 tetrahedra, corners with two equivalent Ni(7)S4 tetrahedra, edges with two equivalent Ni(1)S5 square pyramids, and  an edgeedge with one Ni(5)S4 tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Ni(3), one Ni(4), one Ni(7), and two equivalent Ni(6) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to one Ni(1), one Ni(3), one Ni(5), one Ni(6), and one Ni(8) atom. In the third S site, S(3) is bonded in a distorted pentagonal planar geometry to one Ni(1), one Ni(2), one Ni(4), and two equivalent Ni(6) atoms. In the fourth S site, S(4) is bonded to one Ni(7), one Ni(8), and three equivalent Ni(1) atoms to form a mixture of distorted corner, face, and edge-sharing SNi5 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni9S8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.201
_cell_length_b   7.201
_cell_length_c   9.314
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   79.432
_symmetry_Int_Tables_number   1
_cell_volume   474.785
_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
  Ni  Ni0  1  0.714  0.462  0.373  1.0
  Ni  Ni1  1  0.286  0.538  0.373  1.0
  Ni  Ni2  1  0.538  0.286  0.627  1.0
  Ni  Ni3  1  0.462  0.714  0.627  1.0
  Ni  Ni4  1  0.500  0.500  0.000  1.0
  Ni  Ni5  1  0.000  0.000  0.214  1.0
  Ni  Ni6  1  0.000  0.000  0.786  1.0
  Ni  Ni7  1  0.222  0.778  0.000  1.0
  Ni  Ni8  1  0.778  0.222  0.000  1.0
  Ni  Ni9  1  0.000  0.000  0.500  1.0
  Ni  Ni10  1  0.057  0.309  0.122  1.0
  Ni  Ni11  1  0.943  0.691  0.122  1.0
  Ni  Ni12  1  0.691  0.943  0.878  1.0
  Ni  Ni13  1  0.309  0.057  0.878  1.0
  Ni  Ni14  1  0.500  0.000  0.270  1.0
  Ni  Ni15  1  0.000  0.500  0.730  1.0
  Ni  Ni16  1  0.237  0.237  0.500  1.0
  Ni  Ni17  1  0.763  0.763  0.500  1.0
  S  S18  1  0.730  0.967  0.119  1.0
  S  S19  1  0.270  0.033  0.119  1.0
  S  S20  1  0.033  0.270  0.881  1.0
  S  S21  1  0.967  0.730  0.881  1.0
  S  S22  1  0.983  0.248  0.360  1.0
  S  S23  1  0.017  0.752  0.360  1.0
  S  S24  1  0.752  0.017  0.640  1.0
  S  S25  1  0.248  0.983  0.640  1.0
  S  S26  1  0.749  0.484  0.134  1.0
  S  S27  1  0.251  0.516  0.134  1.0
  S  S28  1  0.516  0.251  0.866  1.0
  S  S29  1  0.484  0.749  0.866  1.0
  S  S30  1  0.498  0.259  0.386  1.0
  S  S31  1  0.502  0.741  0.386  1.0
  S  S32  1  0.741  0.502  0.614  1.0
  S  S33  1  0.259  0.498  0.614  1.0
[/CIF]
.