The compound described by Cr3Ni(SO4)6 crystallizes in the trigonal R3 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent O(1) and three equivalent O(6) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. Ni(1) is bonded to three equivalent O(2) and three equivalent O(4) 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(6), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one Cr(3)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-43°. In the second S site, S(2) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one Cr(3)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-44°. There are eight inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Ni(1) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(2) atom. In the fourth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(2) atom. In the fifth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the sixth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(2) atom. In the seventh O site, O(8) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the eighth O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr3Ni(SO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.843
_cell_length_b   8.843
_cell_length_c   8.843
_cell_angle_alpha   55.938
_cell_angle_beta   55.938
_cell_angle_gamma   55.938
_symmetry_Int_Tables_number   1
_cell_volume   442.931
_cell_formula_units_Z   1
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
  Cr  Cr0  1  0.356  0.356  0.356  1.0
  Cr  Cr1  1  0.644  0.644  0.644  1.0
  Cr  Cr2  1  0.849  0.849  0.849  1.0
  Ni  Ni3  1  0.150  0.150  0.150  1.0
  S  S4  1  0.748  0.040  0.464  1.0
  S  S5  1  0.958  0.538  0.253  1.0
  S  S6  1  0.538  0.253  0.958  1.0
  S  S7  1  0.464  0.748  0.040  1.0
  S  S8  1  0.040  0.464  0.748  1.0
  S  S9  1  0.253  0.958  0.538  1.0
  O  O10  1  0.515  0.299  0.108  1.0
  O  O11  1  0.299  0.108  0.515  1.0
  O  O12  1  0.951  0.010  0.330  1.0
  O  O13  1  0.715  0.024  0.657  1.0
  O  O14  1  0.970  0.349  0.286  1.0
  O  O15  1  0.675  0.047  0.984  1.0
  O  O16  1  0.108  0.515  0.299  1.0
  O  O17  1  0.616  0.238  0.381  1.0
  O  O18  1  0.984  0.675  0.047  1.0
  O  O19  1  0.627  0.382  0.759  1.0
  O  O20  1  0.759  0.627  0.382  1.0
  O  O21  1  0.349  0.286  0.970  1.0
  O  O22  1  0.657  0.715  0.024  1.0
  O  O23  1  0.238  0.381  0.616  1.0
  O  O24  1  0.381  0.616  0.238  1.0
  O  O25  1  0.010  0.330  0.951  1.0
  O  O26  1  0.382  0.759  0.627  1.0
  O  O27  1  0.893  0.491  0.693  1.0
  O  O28  1  0.330  0.951  0.010  1.0
  O  O29  1  0.024  0.657  0.715  1.0
  O  O30  1  0.286  0.970  0.349  1.0
  O  O31  1  0.047  0.984  0.675  1.0
  O  O32  1  0.693  0.893  0.491  1.0
  O  O33  1  0.491  0.693  0.893  1.0
[/CIF]
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The compound described by Cr3Ni(SO4)6 crystallizes in the trigonal R3 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent O(1) and three equivalent O(6) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. In the third Cr site, Cr(3) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form CrO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra and corners with three equivalent S(2)O4 tetrahedra. Ni(1) is bonded to three equivalent O(2) and three equivalent O(4) 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(6), and one O(8) atom to form SO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one Cr(3)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-43°. In the second S site, S(2) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form SO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one Cr(3)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-44°. There are eight inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Ni(1) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one S(2) atom. In the fourth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(3) and one S(2) atom. In the fifth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the sixth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(2) atom. In the seventh O site, O(8) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the eighth O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr3Ni(SO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.843
_cell_length_b   8.843
_cell_length_c   8.843
_cell_angle_alpha   55.938
_cell_angle_beta   55.938
_cell_angle_gamma   55.938
_symmetry_Int_Tables_number   1
_cell_volume   442.931
_cell_formula_units_Z   1
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
  Cr  Cr0  1  0.356  0.356  0.356  1.0
  Cr  Cr1  1  0.644  0.644  0.644  1.0
  Cr  Cr2  1  0.849  0.849  0.849  1.0
  Ni  Ni3  1  0.150  0.150  0.150  1.0
  S  S4  1  0.748  0.040  0.464  1.0
  S  S5  1  0.958  0.538  0.253  1.0
  S  S6  1  0.538  0.253  0.958  1.0
  S  S7  1  0.464  0.748  0.040  1.0
  S  S8  1  0.040  0.464  0.748  1.0
  S  S9  1  0.253  0.958  0.538  1.0
  O  O10  1  0.515  0.299  0.108  1.0
  O  O11  1  0.299  0.108  0.515  1.0
  O  O12  1  0.951  0.010  0.330  1.0
  O  O13  1  0.715  0.024  0.657  1.0
  O  O14  1  0.970  0.349  0.286  1.0
  O  O15  1  0.675  0.047  0.984  1.0
  O  O16  1  0.108  0.515  0.299  1.0
  O  O17  1  0.616  0.238  0.381  1.0
  O  O18  1  0.984  0.675  0.047  1.0
  O  O19  1  0.627  0.382  0.759  1.0
  O  O20  1  0.759  0.627  0.382  1.0
  O  O21  1  0.349  0.286  0.970  1.0
  O  O22  1  0.657  0.715  0.024  1.0
  O  O23  1  0.238  0.381  0.616  1.0
  O  O24  1  0.381  0.616  0.238  1.0
  O  O25  1  0.010  0.330  0.951  1.0
  O  O26  1  0.382  0.759  0.627  1.0
  O  O27  1  0.893  0.491  0.693  1.0
  O  O28  1  0.330  0.951  0.010  1.0
  O  O29  1  0.024  0.657  0.715  1.0
  O  O30  1  0.286  0.970  0.349  1.0
  O  O31  1  0.047  0.984  0.675  1.0
  O  O32  1  0.693  0.893  0.491  1.0
  O  O33  1  0.491  0.693  0.893  1.0
[/CIF]
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