The crystal structure described by KAlSiO4 crystallizes in the triclinic P1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and three equivalent O(7) atoms. In the second K site, K(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and three equivalent O(8) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(3), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Al(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra and corners with three equivalent Al(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to three equivalent K(1), one Al(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to three equivalent K(2), one Al(2), and one Si(2) atom. is represented by the CIF card [CIF]
data_KAlSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.219
_cell_length_b   5.240
_cell_length_c   8.849
_cell_angle_alpha   90.636
_cell_angle_beta   89.609
_cell_angle_gamma   119.789
_symmetry_Int_Tables_number   1
_cell_volume   209.992
_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  0.003  0.003  0.259  1.0
  K  K1  1  0.002  0.999  0.759  1.0
  Al  Al2  1  0.340  0.670  0.453  1.0
  Al  Al3  1  0.675  0.336  0.953  1.0
  Si  Si4  1  0.341  0.672  0.071  1.0
  Si  Si5  1  0.673  0.335  0.571  1.0
  O  O6  1  0.605  0.986  0.007  1.0
  O  O7  1  0.016  0.619  0.020  1.0
  O  O8  1  0.388  0.401  0.011  1.0
  O  O9  1  0.400  0.015  0.518  1.0
  O  O10  1  0.987  0.383  0.503  1.0
  O  O11  1  0.618  0.603  0.518  1.0
  O  O12  1  0.357  0.685  0.255  1.0
  O  O13  1  0.691  0.341  0.755  1.0
[/CIF]
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The crystal structure described by KAlSiO4 crystallizes in the triclinic P1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and three equivalent O(7) atoms. In the second K site, K(2) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and three equivalent O(8) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(2), one O(3), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Al(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra and corners with three equivalent Al(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one K(1), one K(2), one Al(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to three equivalent K(1), one Al(1), and one Si(1) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to three equivalent K(2), one Al(2), and one Si(2) atom. is represented by the CIF card [CIF]
data_KAlSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.219
_cell_length_b   5.240
_cell_length_c   8.849
_cell_angle_alpha   90.636
_cell_angle_beta   89.609
_cell_angle_gamma   119.789
_symmetry_Int_Tables_number   1
_cell_volume   209.992
_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  0.003  0.003  0.259  1.0
  K  K1  1  0.002  0.999  0.759  1.0
  Al  Al2  1  0.340  0.670  0.453  1.0
  Al  Al3  1  0.675  0.336  0.953  1.0
  Si  Si4  1  0.341  0.672  0.071  1.0
  Si  Si5  1  0.673  0.335  0.571  1.0
  O  O6  1  0.605  0.986  0.007  1.0
  O  O7  1  0.016  0.619  0.020  1.0
  O  O8  1  0.388  0.401  0.011  1.0
  O  O9  1  0.400  0.015  0.518  1.0
  O  O10  1  0.987  0.383  0.503  1.0
  O  O11  1  0.618  0.603  0.518  1.0
  O  O12  1  0.357  0.685  0.255  1.0
  O  O13  1  0.691  0.341  0.755  1.0
[/CIF]
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