The crystal structure described by KAl3(SO7)2 crystallizes in the trigonal R-3m space group. K(1) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form KO12 cuboctahedra that share corners with six equivalent S(1)O4 tetrahedra and faces with six equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, and faces with two equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 38°. S(1) is bonded to one O(1) and three equivalent O(2) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one S(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_KAl3(SO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.423
_cell_length_b   7.423
_cell_length_c   7.423
_cell_angle_alpha   56.286
_cell_angle_beta   56.286
_cell_angle_gamma   56.286
_symmetry_Int_Tables_number   1
_cell_volume   264.310
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.000  0.500  1.0
  Al  Al2  1  0.500  0.000  0.000  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  S  S4  1  0.701  0.701  0.701  1.0
  S  S5  1  0.299  0.299  0.299  1.0
  O  O6  1  0.624  0.624  0.624  1.0
  O  O7  1  0.376  0.376  0.376  1.0
  O  O8  1  0.847  0.847  0.499  1.0
  O  O9  1  0.499  0.847  0.847  1.0
  O  O10  1  0.847  0.499  0.847  1.0
  O  O11  1  0.153  0.153  0.501  1.0
  O  O12  1  0.501  0.153  0.153  1.0
  O  O13  1  0.153  0.501  0.153  1.0
  O  O14  1  0.744  0.744  0.086  1.0
  O  O15  1  0.086  0.744  0.744  1.0
  O  O16  1  0.744  0.086  0.744  1.0
  O  O17  1  0.256  0.256  0.914  1.0
  O  O18  1  0.914  0.256  0.256  1.0
  O  O19  1  0.256  0.914  0.256  1.0
[/CIF]
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The crystal structure described by KAl3(SO7)2 crystallizes in the trigonal R-3m space group. K(1) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form KO12 cuboctahedra that share corners with six equivalent S(1)O4 tetrahedra and faces with six equivalent Al(1)O6 octahedra. Al(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form AlO6 octahedra that share corners with four equivalent Al(1)O6 octahedra, corners with two equivalent S(1)O4 tetrahedra, and faces with two equivalent K(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 38°. S(1) is bonded to one O(1) and three equivalent O(2) atoms to form SO4 tetrahedra that share corners with three equivalent K(1)O12 cuboctahedra and corners with three equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one S(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one S(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1) and two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_KAl3(SO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.423
_cell_length_b   7.423
_cell_length_c   7.423
_cell_angle_alpha   56.286
_cell_angle_beta   56.286
_cell_angle_gamma   56.286
_symmetry_Int_Tables_number   1
_cell_volume   264.310
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.000  0.500  1.0
  Al  Al2  1  0.500  0.000  0.000  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  S  S4  1  0.701  0.701  0.701  1.0
  S  S5  1  0.299  0.299  0.299  1.0
  O  O6  1  0.624  0.624  0.624  1.0
  O  O7  1  0.376  0.376  0.376  1.0
  O  O8  1  0.847  0.847  0.499  1.0
  O  O9  1  0.499  0.847  0.847  1.0
  O  O10  1  0.847  0.499  0.847  1.0
  O  O11  1  0.153  0.153  0.501  1.0
  O  O12  1  0.501  0.153  0.153  1.0
  O  O13  1  0.153  0.501  0.153  1.0
  O  O14  1  0.744  0.744  0.086  1.0
  O  O15  1  0.086  0.744  0.744  1.0
  O  O16  1  0.744  0.086  0.744  1.0
  O  O17  1  0.256  0.256  0.914  1.0
  O  O18  1  0.914  0.256  0.256  1.0
  O  O19  1  0.256  0.914  0.256  1.0
[/CIF]
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