The material structure described by KAlSiO4 crystallizes in the trigonal P31c space group. K(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(2) atoms. Al(1) is bonded to one O(1) and three equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1) and three equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to three equivalent K(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Al(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAlSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.230
_cell_length_b   5.230
_cell_length_c   8.858
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   209.804
_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
  K  K0  1  0.000  0.000  0.754  1.0
  K  K1  1  0.000  0.000  0.254  1.0
  Al  Al2  1  0.333  0.667  0.060  1.0
  Al  Al3  1  0.667  0.333  0.560  1.0
  Si  Si4  1  0.667  0.333  0.942  1.0
  Si  Si5  1  0.333  0.667  0.442  1.0
  O  O6  1  0.667  0.333  0.757  1.0
  O  O7  1  0.333  0.667  0.257  1.0
  O  O8  1  0.382  0.397  0.500  1.0
  O  O9  1  0.603  0.986  0.500  1.0
  O  O10  1  0.014  0.618  0.500  1.0
  O  O11  1  0.397  0.382  1.000  1.0
  O  O12  1  0.618  0.014  1.000  1.0
  O  O13  1  0.986  0.603  1.000  1.0
[/CIF]
.
The material structure described by KAlSiO4 crystallizes in the trigonal P31c space group. K(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(2) atoms. Al(1) is bonded to one O(1) and three equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1) and three equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to three equivalent K(1), one Al(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Al(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAlSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.230
_cell_length_b   5.230
_cell_length_c   8.858
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   209.804
_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
  K  K0  1  0.000  0.000  0.754  1.0
  K  K1  1  0.000  0.000  0.254  1.0
  Al  Al2  1  0.333  0.667  0.060  1.0
  Al  Al3  1  0.667  0.333  0.560  1.0
  Si  Si4  1  0.667  0.333  0.942  1.0
  Si  Si5  1  0.333  0.667  0.442  1.0
  O  O6  1  0.667  0.333  0.757  1.0
  O  O7  1  0.333  0.667  0.257  1.0
  O  O8  1  0.382  0.397  0.500  1.0
  O  O9  1  0.603  0.986  0.500  1.0
  O  O10  1  0.014  0.618  0.500  1.0
  O  O11  1  0.397  0.382  1.000  1.0
  O  O12  1  0.618  0.014  1.000  1.0
  O  O13  1  0.986  0.603  1.000  1.0
[/CIF]
.