The structure described by Ni(SO4)2 crystallizes in the trigonal R3 space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Ni site, Ni(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  a cornercorner with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-44°. In the second S site, S(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  a cornercorner with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-46°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(5) is bonded in a bent 150 degrees geometry to one Ni(3) and one S(2) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(2) atom. In the fourth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one S(2) atom. In the fifth O site, O(8) is bonded in a bent 150 degrees geometry to one Ni(2) and one S(1) atom. In the sixth O site, O(1) is bonded in a single-bond geometry to one S(2) atom. In the seventh O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(1) atom. In the eighth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one S(1) atom. is represented by the CIF file [CIF]
data_Ni(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.931
_cell_length_b   8.931
_cell_length_c   8.931
_cell_angle_alpha   55.425
_cell_angle_beta   55.425
_cell_angle_gamma   55.425
_symmetry_Int_Tables_number   1
_cell_volume   450.142
_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
  Ni  Ni0  1  0.151  0.151  0.151  1.0
  Ni  Ni1  1  0.644  0.644  0.644  1.0
  Ni  Ni2  1  0.849  0.849  0.849  1.0
  S  S3  1  0.041  0.757  0.456  1.0
  S  S4  1  0.456  0.041  0.757  1.0
  S  S5  1  0.757  0.456  0.041  1.0
  S  S6  1  0.248  0.542  0.956  1.0
  S  S7  1  0.542  0.956  0.248  1.0
  S  S8  1  0.956  0.248  0.542  1.0
  O  O9  1  0.109  0.296  0.507  1.0
  O  O10  1  0.296  0.507  0.109  1.0
  O  O11  1  0.998  0.967  0.332  1.0
  O  O12  1  0.507  0.109  0.296  1.0
  O  O13  1  0.026  0.718  0.650  1.0
  O  O14  1  0.243  0.639  0.366  1.0
  O  O15  1  0.366  0.243  0.639  1.0
  O  O16  1  0.332  0.998  0.967  1.0
  O  O17  1  0.639  0.366  0.243  1.0
  O  O18  1  0.040  0.671  0.992  1.0
  O  O19  1  0.283  0.350  0.970  1.0
  O  O20  1  0.350  0.970  0.283  1.0
  O  O21  1  0.650  0.026  0.718  1.0
  O  O22  1  0.718  0.650  0.026  1.0
  O  O23  1  0.967  0.332  0.998  1.0
  O  O24  1  0.374  0.630  0.759  1.0
  O  O25  1  0.671  0.992  0.040  1.0
  O  O26  1  0.630  0.759  0.374  1.0
  O  O27  1  0.759  0.374  0.630  1.0
  O  O28  1  0.970  0.283  0.350  1.0
  O  O29  1  0.480  0.902  0.698  1.0
  O  O30  1  0.992  0.040  0.671  1.0
  O  O31  1  0.698  0.480  0.902  1.0
  O  O32  1  0.902  0.698  0.480  1.0
[/CIF]
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The structure described by Ni(SO4)2 crystallizes in the trigonal R3 space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Ni site, Ni(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form NiO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  a cornercorner with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-44°. In the second S site, S(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  a cornercorner with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-46°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(5) is bonded in a bent 150 degrees geometry to one Ni(3) and one S(2) atom. In the third O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(2) atom. In the fourth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one S(2) atom. In the fifth O site, O(8) is bonded in a bent 150 degrees geometry to one Ni(2) and one S(1) atom. In the sixth O site, O(1) is bonded in a single-bond geometry to one S(2) atom. In the seventh O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(1) atom. In the eighth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one S(1) atom. is represented by the CIF file [CIF]
data_Ni(SO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.931
_cell_length_b   8.931
_cell_length_c   8.931
_cell_angle_alpha   55.425
_cell_angle_beta   55.425
_cell_angle_gamma   55.425
_symmetry_Int_Tables_number   1
_cell_volume   450.142
_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
  Ni  Ni0  1  0.151  0.151  0.151  1.0
  Ni  Ni1  1  0.644  0.644  0.644  1.0
  Ni  Ni2  1  0.849  0.849  0.849  1.0
  S  S3  1  0.041  0.757  0.456  1.0
  S  S4  1  0.456  0.041  0.757  1.0
  S  S5  1  0.757  0.456  0.041  1.0
  S  S6  1  0.248  0.542  0.956  1.0
  S  S7  1  0.542  0.956  0.248  1.0
  S  S8  1  0.956  0.248  0.542  1.0
  O  O9  1  0.109  0.296  0.507  1.0
  O  O10  1  0.296  0.507  0.109  1.0
  O  O11  1  0.998  0.967  0.332  1.0
  O  O12  1  0.507  0.109  0.296  1.0
  O  O13  1  0.026  0.718  0.650  1.0
  O  O14  1  0.243  0.639  0.366  1.0
  O  O15  1  0.366  0.243  0.639  1.0
  O  O16  1  0.332  0.998  0.967  1.0
  O  O17  1  0.639  0.366  0.243  1.0
  O  O18  1  0.040  0.671  0.992  1.0
  O  O19  1  0.283  0.350  0.970  1.0
  O  O20  1  0.350  0.970  0.283  1.0
  O  O21  1  0.650  0.026  0.718  1.0
  O  O22  1  0.718  0.650  0.026  1.0
  O  O23  1  0.967  0.332  0.998  1.0
  O  O24  1  0.374  0.630  0.759  1.0
  O  O25  1  0.671  0.992  0.040  1.0
  O  O26  1  0.630  0.759  0.374  1.0
  O  O27  1  0.759  0.374  0.630  1.0
  O  O28  1  0.970  0.283  0.350  1.0
  O  O29  1  0.480  0.902  0.698  1.0
  O  O30  1  0.992  0.040  0.671  1.0
  O  O31  1  0.698  0.480  0.902  1.0
  O  O32  1  0.902  0.698  0.480  1.0
[/CIF]
.