The crystal structure described by Al2(SeO4)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(1) and three equivalent O(4) atoms to form AlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form AlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 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 30-46°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Al(2) and one Se(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Al(1) and one Se(1) atom. In the third O site, O(1) is bonded in a bent 150 degrees geometry to one Al(1) and one Se(1) atom. In the fourth O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Al(2) and one Se(1) atom. is represented by the CIF file [CIF]
data_Al2(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.827
_cell_length_b   8.827
_cell_length_c   8.827
_cell_angle_alpha   56.187
_cell_angle_beta   56.187
_cell_angle_gamma   56.187
_symmetry_Int_Tables_number   1
_cell_volume   443.331
_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  0.648  0.648  0.648  1.0
  Al  Al1  1  0.858  0.858  0.858  1.0
  Al  Al2  1  0.142  0.142  0.142  1.0
  Al  Al3  1  0.352  0.352  0.352  1.0
  Se  Se4  1  0.967  0.538  0.249  1.0
  Se  Se5  1  0.538  0.249  0.967  1.0
  Se  Se6  1  0.249  0.967  0.538  1.0
  Se  Se7  1  0.751  0.033  0.462  1.0
  Se  Se8  1  0.462  0.751  0.033  1.0
  Se  Se9  1  0.033  0.462  0.751  1.0
  O  O10  1  0.814  0.509  0.476  1.0
  O  O11  1  0.877  0.756  0.103  1.0
  O  O12  1  0.989  0.371  0.201  1.0
  O  O13  1  0.518  0.210  0.182  1.0
  O  O14  1  0.756  0.103  0.877  1.0
  O  O15  1  0.509  0.476  0.814  1.0
  O  O16  1  0.476  0.814  0.509  1.0
  O  O17  1  0.210  0.182  0.518  1.0
  O  O18  1  0.799  0.011  0.629  1.0
  O  O19  1  0.182  0.518  0.210  1.0
  O  O20  1  0.897  0.123  0.244  1.0
  O  O21  1  0.629  0.799  0.011  1.0
  O  O22  1  0.371  0.201  0.989  1.0
  O  O23  1  0.103  0.877  0.756  1.0
  O  O24  1  0.818  0.482  0.790  1.0
  O  O25  1  0.201  0.989  0.371  1.0
  O  O26  1  0.790  0.818  0.482  1.0
  O  O27  1  0.524  0.186  0.491  1.0
  O  O28  1  0.491  0.524  0.186  1.0
  O  O29  1  0.244  0.897  0.123  1.0
  O  O30  1  0.482  0.790  0.818  1.0
  O  O31  1  0.011  0.629  0.799  1.0
  O  O32  1  0.123  0.244  0.897  1.0
  O  O33  1  0.186  0.491  0.524  1.0
[/CIF]
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The crystal structure described by Al2(SeO4)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(1) and three equivalent O(4) atoms to form AlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form AlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 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 30-46°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a bent 150 degrees geometry to one Al(2) and one Se(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Al(1) and one Se(1) atom. In the third O site, O(1) is bonded in a bent 150 degrees geometry to one Al(1) and one Se(1) atom. In the fourth O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Al(2) and one Se(1) atom. is represented by the CIF file [CIF]
data_Al2(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.827
_cell_length_b   8.827
_cell_length_c   8.827
_cell_angle_alpha   56.187
_cell_angle_beta   56.187
_cell_angle_gamma   56.187
_symmetry_Int_Tables_number   1
_cell_volume   443.331
_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  0.648  0.648  0.648  1.0
  Al  Al1  1  0.858  0.858  0.858  1.0
  Al  Al2  1  0.142  0.142  0.142  1.0
  Al  Al3  1  0.352  0.352  0.352  1.0
  Se  Se4  1  0.967  0.538  0.249  1.0
  Se  Se5  1  0.538  0.249  0.967  1.0
  Se  Se6  1  0.249  0.967  0.538  1.0
  Se  Se7  1  0.751  0.033  0.462  1.0
  Se  Se8  1  0.462  0.751  0.033  1.0
  Se  Se9  1  0.033  0.462  0.751  1.0
  O  O10  1  0.814  0.509  0.476  1.0
  O  O11  1  0.877  0.756  0.103  1.0
  O  O12  1  0.989  0.371  0.201  1.0
  O  O13  1  0.518  0.210  0.182  1.0
  O  O14  1  0.756  0.103  0.877  1.0
  O  O15  1  0.509  0.476  0.814  1.0
  O  O16  1  0.476  0.814  0.509  1.0
  O  O17  1  0.210  0.182  0.518  1.0
  O  O18  1  0.799  0.011  0.629  1.0
  O  O19  1  0.182  0.518  0.210  1.0
  O  O20  1  0.897  0.123  0.244  1.0
  O  O21  1  0.629  0.799  0.011  1.0
  O  O22  1  0.371  0.201  0.989  1.0
  O  O23  1  0.103  0.877  0.756  1.0
  O  O24  1  0.818  0.482  0.790  1.0
  O  O25  1  0.201  0.989  0.371  1.0
  O  O26  1  0.790  0.818  0.482  1.0
  O  O27  1  0.524  0.186  0.491  1.0
  O  O28  1  0.491  0.524  0.186  1.0
  O  O29  1  0.244  0.897  0.123  1.0
  O  O30  1  0.482  0.790  0.818  1.0
  O  O31  1  0.011  0.629  0.799  1.0
  O  O32  1  0.123  0.244  0.897  1.0
  O  O33  1  0.186  0.491  0.524  1.0
[/CIF]
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