The crystal structure described by NiS2 is Pyrite-like structured and crystallizes in the orthorhombic Pnma space group. Ni(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form NiS6 octahedra that share corners with four equivalent Ni(1)S6 octahedra, corners with three equivalent S(1)Ni3S tetrahedra, corners with three equivalent S(2)Ni3S tetrahedra, and edges with four equivalent Ni(1)S6 octahedra. The corner-sharing octahedral tilt angles are 65°. There are two inequivalent S sites. In the first S site, S(2) is bonded to three equivalent Ni(1) and one S(1) atom to form distorted SNi3S tetrahedra that share corners with three equivalent Ni(1)S6 octahedra, corners with two equivalent S(2)Ni3S tetrahedra, corners with seven equivalent S(1)Ni3S tetrahedra,  an edgeedge with one S(1)Ni3S tetrahedra, and edges with two equivalent S(2)Ni3S tetrahedra. The corner-sharing octahedral tilt angles range from 67-73°. In the second S site, S(1) is bonded to three equivalent Ni(1) and one S(2) atom to form distorted SNi3S tetrahedra that share corners with three equivalent Ni(1)S6 octahedra, corners with six equivalent S(1)Ni3S tetrahedra, corners with seven equivalent S(2)Ni3S tetrahedra, and  an edgeedge with one S(2)Ni3S tetrahedra. The corner-sharing octahedral tilt angles range from 56-73°. is represented by the CIF file [CIF]
data_NiS2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.569
_cell_length_b   5.767
_cell_length_c   9.106
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.390
_cell_formula_units_Z   4
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  0.250  0.333  0.866  1.0
  Ni  Ni1  1  0.250  0.167  0.366  1.0
  Ni  Ni2  1  0.750  0.667  0.134  1.0
  Ni  Ni3  1  0.750  0.833  0.634  1.0
  S  S4  1  0.250  0.940  0.790  1.0
  S  S5  1  0.250  0.560  0.290  1.0
  S  S6  1  0.750  0.060  0.210  1.0
  S  S7  1  0.750  0.440  0.710  1.0
  S  S8  1  0.750  0.208  0.533  1.0
  S  S9  1  0.750  0.292  0.033  1.0
  S  S10  1  0.250  0.792  0.467  1.0
  S  S11  1  0.250  0.708  0.967  1.0
[/CIF]
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The crystal structure described by NiS2 is Pyrite-like structured and crystallizes in the orthorhombic Pnma space group. Ni(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form NiS6 octahedra that share corners with four equivalent Ni(1)S6 octahedra, corners with three equivalent S(1)Ni3S tetrahedra, corners with three equivalent S(2)Ni3S tetrahedra, and edges with four equivalent Ni(1)S6 octahedra. The corner-sharing octahedral tilt angles are 65°. There are two inequivalent S sites. In the first S site, S(2) is bonded to three equivalent Ni(1) and one S(1) atom to form distorted SNi3S tetrahedra that share corners with three equivalent Ni(1)S6 octahedra, corners with two equivalent S(2)Ni3S tetrahedra, corners with seven equivalent S(1)Ni3S tetrahedra,  an edgeedge with one S(1)Ni3S tetrahedra, and edges with two equivalent S(2)Ni3S tetrahedra. The corner-sharing octahedral tilt angles range from 67-73°. In the second S site, S(1) is bonded to three equivalent Ni(1) and one S(2) atom to form distorted SNi3S tetrahedra that share corners with three equivalent Ni(1)S6 octahedra, corners with six equivalent S(1)Ni3S tetrahedra, corners with seven equivalent S(2)Ni3S tetrahedra, and  an edgeedge with one S(2)Ni3S tetrahedra. The corner-sharing octahedral tilt angles range from 56-73°. is represented by the CIF file [CIF]
data_NiS2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.569
_cell_length_b   5.767
_cell_length_c   9.106
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.390
_cell_formula_units_Z   4
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  0.250  0.333  0.866  1.0
  Ni  Ni1  1  0.250  0.167  0.366  1.0
  Ni  Ni2  1  0.750  0.667  0.134  1.0
  Ni  Ni3  1  0.750  0.833  0.634  1.0
  S  S4  1  0.250  0.940  0.790  1.0
  S  S5  1  0.250  0.560  0.290  1.0
  S  S6  1  0.750  0.060  0.210  1.0
  S  S7  1  0.750  0.440  0.710  1.0
  S  S8  1  0.750  0.208  0.533  1.0
  S  S9  1  0.750  0.292  0.033  1.0
  S  S10  1  0.250  0.792  0.467  1.0
  S  S11  1  0.250  0.708  0.967  1.0
[/CIF]
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