The compound described by Al2(SO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form AlO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form AlO6 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 Al(1)O6 octahedra and corners with two equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-38°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the third O site, O(4) is bonded in a bent 150 degrees geometry to one Al(2) and one S(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Al(2) and one S(1) atom. is represented by the CIF file [CIF]
data_Al2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.494
_cell_length_b   8.494
_cell_length_c   8.494
_cell_angle_alpha   56.353
_cell_angle_beta   56.353
_cell_angle_gamma   56.353
_symmetry_Int_Tables_number   1
_cell_volume   396.745
_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
  Al  Al0  1  0.143  0.143  0.143  1.0
  Al  Al1  1  0.857  0.857  0.857  1.0
  Al  Al2  1  0.352  0.352  0.352  1.0
  Al  Al3  1  0.648  0.648  0.648  1.0
  S  S4  1  0.539  0.964  0.248  1.0
  S  S5  1  0.248  0.539  0.964  1.0
  S  S6  1  0.964  0.248  0.539  1.0
  S  S7  1  0.752  0.461  0.036  1.0
  S  S8  1  0.461  0.036  0.752  1.0
  S  S9  1  0.036  0.752  0.461  1.0
  O  O10  1  0.184  0.546  0.476  1.0
  O  O11  1  0.476  0.184  0.546  1.0
  O  O12  1  0.546  0.476  0.184  1.0
  O  O13  1  0.816  0.454  0.524  1.0
  O  O14  1  0.524  0.816  0.454  1.0
  O  O15  1  0.454  0.524  0.816  1.0
  O  O16  1  0.112  0.895  0.264  1.0
  O  O17  1  0.264  0.112  0.895  1.0
  O  O18  1  0.895  0.264  0.112  1.0
  O  O19  1  0.888  0.105  0.736  1.0
  O  O20  1  0.205  0.379  0.993  1.0
  O  O21  1  0.379  0.993  0.205  1.0
  O  O22  1  0.993  0.205  0.379  1.0
  O  O23  1  0.795  0.621  0.007  1.0
  O  O24  1  0.621  0.007  0.795  1.0
  O  O25  1  0.007  0.795  0.621  1.0
  O  O26  1  0.229  0.519  0.156  1.0
  O  O27  1  0.519  0.156  0.229  1.0
  O  O28  1  0.156  0.229  0.519  1.0
  O  O29  1  0.771  0.481  0.844  1.0
  O  O30  1  0.481  0.844  0.771  1.0
  O  O31  1  0.844  0.771  0.481  1.0
  O  O32  1  0.105  0.736  0.888  1.0
  O  O33  1  0.736  0.888  0.105  1.0
[/CIF]
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The compound described by Al2(SO4)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form AlO6 octahedra that share corners with six equivalent S(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form AlO6 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 Al(1)O6 octahedra and corners with two equivalent Al(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-38°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the second O site, O(3) is bonded in a bent 150 degrees geometry to one Al(1) and one S(1) atom. In the third O site, O(4) is bonded in a bent 150 degrees geometry to one Al(2) and one S(1) atom. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to one Al(2) and one S(1) atom. is represented by the CIF file [CIF]
data_Al2(SO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.494
_cell_length_b   8.494
_cell_length_c   8.494
_cell_angle_alpha   56.353
_cell_angle_beta   56.353
_cell_angle_gamma   56.353
_symmetry_Int_Tables_number   1
_cell_volume   396.745
_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
  Al  Al0  1  0.143  0.143  0.143  1.0
  Al  Al1  1  0.857  0.857  0.857  1.0
  Al  Al2  1  0.352  0.352  0.352  1.0
  Al  Al3  1  0.648  0.648  0.648  1.0
  S  S4  1  0.539  0.964  0.248  1.0
  S  S5  1  0.248  0.539  0.964  1.0
  S  S6  1  0.964  0.248  0.539  1.0
  S  S7  1  0.752  0.461  0.036  1.0
  S  S8  1  0.461  0.036  0.752  1.0
  S  S9  1  0.036  0.752  0.461  1.0
  O  O10  1  0.184  0.546  0.476  1.0
  O  O11  1  0.476  0.184  0.546  1.0
  O  O12  1  0.546  0.476  0.184  1.0
  O  O13  1  0.816  0.454  0.524  1.0
  O  O14  1  0.524  0.816  0.454  1.0
  O  O15  1  0.454  0.524  0.816  1.0
  O  O16  1  0.112  0.895  0.264  1.0
  O  O17  1  0.264  0.112  0.895  1.0
  O  O18  1  0.895  0.264  0.112  1.0
  O  O19  1  0.888  0.105  0.736  1.0
  O  O20  1  0.205  0.379  0.993  1.0
  O  O21  1  0.379  0.993  0.205  1.0
  O  O22  1  0.993  0.205  0.379  1.0
  O  O23  1  0.795  0.621  0.007  1.0
  O  O24  1  0.621  0.007  0.795  1.0
  O  O25  1  0.007  0.795  0.621  1.0
  O  O26  1  0.229  0.519  0.156  1.0
  O  O27  1  0.519  0.156  0.229  1.0
  O  O28  1  0.156  0.229  0.519  1.0
  O  O29  1  0.771  0.481  0.844  1.0
  O  O30  1  0.481  0.844  0.771  1.0
  O  O31  1  0.844  0.771  0.481  1.0
  O  O32  1  0.105  0.736  0.888  1.0
  O  O33  1  0.736  0.888  0.105  1.0
[/CIF]
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