The material described by Cr2(SO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form CrO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra and corners with two equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-44°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.126
_cell_length_b   8.126
_cell_length_c   8.704
_cell_angle_alpha   62.171
_cell_angle_beta   117.829
_cell_angle_gamma   120.003
_symmetry_Int_Tables_number   1
_cell_volume   419.204
_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
  Cr  Cr0  1  0.349  0.651  0.047  1.0
  Cr  Cr1  1  0.856  0.144  0.569  1.0
  Cr  Cr2  1  0.651  0.349  0.953  1.0
  Cr  Cr3  1  0.144  0.856  0.431  1.0
  S  S4  1  0.459  0.962  0.248  1.0
  S  S5  1  0.752  0.541  0.248  1.0
  S  S6  1  0.038  0.248  0.248  1.0
  S  S7  1  0.541  0.038  0.752  1.0
  S  S8  1  0.248  0.459  0.752  1.0
  S  S9  1  0.962  0.752  0.752  1.0
  O  O10  1  0.828  0.543  0.799  1.0
  O  O11  1  0.513  0.172  0.799  1.0
  O  O12  1  0.457  0.487  0.799  1.0
  O  O13  1  0.171  0.457  0.201  1.0
  O  O14  1  0.487  0.828  0.201  1.0
  O  O15  1  0.543  0.513  0.201  1.0
  O  O16  1  0.875  0.882  0.733  1.0
  O  O17  1  0.741  0.125  0.733  1.0
  O  O18  1  0.118  0.259  0.733  1.0
  O  O19  1  0.125  0.118  0.267  1.0
  O  O20  1  0.882  0.741  0.267  1.0
  O  O21  1  0.259  0.875  0.267  1.0
  O  O22  1  0.799  0.390  0.422  1.0
  O  O23  1  0.610  0.987  0.422  1.0
  O  O24  1  0.013  0.201  0.422  1.0
  O  O25  1  0.201  0.610  0.578  1.0
  O  O26  1  0.390  0.013  0.578  1.0
  O  O27  1  0.987  0.799  0.578  1.0
  O  O28  1  0.787  0.525  0.105  1.0
  O  O29  1  0.475  0.157  0.105  1.0
  O  O30  1  0.843  0.213  0.105  1.0
  O  O31  1  0.213  0.475  0.895  1.0
  O  O32  1  0.525  0.843  0.896  1.0
  O  O33  1  0.157  0.787  0.895  1.0
[/CIF]
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The material described by Cr2(SO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form CrO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form CrO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra and corners with two equivalent Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-44°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(2) and one S(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one S(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(1) and one S(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.126
_cell_length_b   8.126
_cell_length_c   8.704
_cell_angle_alpha   62.171
_cell_angle_beta   117.829
_cell_angle_gamma   120.003
_symmetry_Int_Tables_number   1
_cell_volume   419.204
_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
  Cr  Cr0  1  0.349  0.651  0.047  1.0
  Cr  Cr1  1  0.856  0.144  0.569  1.0
  Cr  Cr2  1  0.651  0.349  0.953  1.0
  Cr  Cr3  1  0.144  0.856  0.431  1.0
  S  S4  1  0.459  0.962  0.248  1.0
  S  S5  1  0.752  0.541  0.248  1.0
  S  S6  1  0.038  0.248  0.248  1.0
  S  S7  1  0.541  0.038  0.752  1.0
  S  S8  1  0.248  0.459  0.752  1.0
  S  S9  1  0.962  0.752  0.752  1.0
  O  O10  1  0.828  0.543  0.799  1.0
  O  O11  1  0.513  0.172  0.799  1.0
  O  O12  1  0.457  0.487  0.799  1.0
  O  O13  1  0.171  0.457  0.201  1.0
  O  O14  1  0.487  0.828  0.201  1.0
  O  O15  1  0.543  0.513  0.201  1.0
  O  O16  1  0.875  0.882  0.733  1.0
  O  O17  1  0.741  0.125  0.733  1.0
  O  O18  1  0.118  0.259  0.733  1.0
  O  O19  1  0.125  0.118  0.267  1.0
  O  O20  1  0.882  0.741  0.267  1.0
  O  O21  1  0.259  0.875  0.267  1.0
  O  O22  1  0.799  0.390  0.422  1.0
  O  O23  1  0.610  0.987  0.422  1.0
  O  O24  1  0.013  0.201  0.422  1.0
  O  O25  1  0.201  0.610  0.578  1.0
  O  O26  1  0.390  0.013  0.578  1.0
  O  O27  1  0.987  0.799  0.578  1.0
  O  O28  1  0.787  0.525  0.105  1.0
  O  O29  1  0.475  0.157  0.105  1.0
  O  O30  1  0.843  0.213  0.105  1.0
  O  O31  1  0.213  0.475  0.895  1.0
  O  O32  1  0.525  0.843  0.896  1.0
  O  O33  1  0.157  0.787  0.895  1.0
[/CIF]
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