The material structure described by KAl4(SiO6)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form KO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and corners with six equivalent Si(1)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AlO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra and corners with three equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 70-75°. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra and corners with three equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 66-71°. There are six inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to one Al(1) and two equivalent Al(2) atoms. In the second O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one Si(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one Al(1), and one Si(1) atom. In the fourth O site, O(5) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one Si(1) atom. In the fifth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Al(2) and one O(6) atom. In the sixth O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Al(2) and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAl4(SiO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.413
_cell_length_b   5.413
_cell_length_c   20.667
_cell_angle_alpha   87.397
_cell_angle_beta   87.397
_cell_angle_gamma   120.036
_symmetry_Int_Tables_number   1
_cell_volume   521.974
_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  0.098  0.902  0.750  1.0
  K  K1  1  0.902  0.098  0.250  1.0
  Al  Al2  1  0.812  0.278  0.637  1.0
  Al  Al3  1  0.722  0.188  0.863  1.0
  Al  Al4  1  0.188  0.722  0.363  1.0
  Al  Al5  1  0.278  0.812  0.137  1.0
  Al  Al6  1  0.797  0.584  0.500  1.0
  Al  Al7  1  0.416  0.203  0.000  1.0
  Al  Al8  1  0.203  0.416  0.500  1.0
  Al  Al9  1  0.584  0.797  1.000  1.0
  Si  Si10  1  0.472  0.592  0.638  1.0
  Si  Si11  1  0.408  0.528  0.862  1.0
  Si  Si12  1  0.528  0.408  0.362  1.0
  Si  Si13  1  0.592  0.472  0.138  1.0
  O  O14  1  0.495  0.571  0.555  1.0
  O  O15  1  0.429  0.505  0.945  1.0
  O  O16  1  0.505  0.429  0.445  1.0
  O  O17  1  0.571  0.495  0.055  1.0
  O  O18  1  0.890  0.370  0.552  1.0
  O  O19  1  0.630  0.110  0.948  1.0
  O  O20  1  0.110  0.630  0.448  1.0
  O  O21  1  0.370  0.890  0.052  1.0
  O  O22  1  0.684  0.493  0.667  1.0
  O  O23  1  0.507  0.316  0.833  1.0
  O  O24  1  0.316  0.507  0.333  1.0
  O  O25  1  0.493  0.684  0.167  1.0
  O  O26  1  0.565  0.915  0.654  1.0
  O  O27  1  0.085  0.435  0.846  1.0
  O  O28  1  0.435  0.085  0.346  1.0
  O  O29  1  0.915  0.565  0.154  1.0
  O  O30  1  0.144  0.371  0.666  1.0
  O  O31  1  0.629  0.856  0.834  1.0
  O  O32  1  0.856  0.629  0.334  1.0
  O  O33  1  0.371  0.144  0.166  1.0
  O  O34  1  0.064  0.989  0.527  1.0
  O  O35  1  0.011  0.936  0.973  1.0
  O  O36  1  0.936  0.011  0.473  1.0
  O  O37  1  0.989  0.064  0.027  1.0
[/CIF]
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The material structure described by KAl4(SiO6)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form KO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and corners with six equivalent Si(1)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form AlO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra and corners with three equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 70-75°. In the second Al site, Al(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with three equivalent K(1)O6 octahedra and corners with three equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 66-71°. There are six inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to one Al(1) and two equivalent Al(2) atoms. In the second O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one Si(1) atom. In the third O site, O(4) is bonded in a distorted bent 150 degrees geometry to one K(1), one Al(1), and one Si(1) atom. In the fourth O site, O(5) is bonded in a 2-coordinate geometry to one K(1), one Al(1), and one Si(1) atom. In the fifth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Al(2) and one O(6) atom. In the sixth O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Al(2) and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAl4(SiO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.413
_cell_length_b   5.413
_cell_length_c   20.667
_cell_angle_alpha   87.397
_cell_angle_beta   87.397
_cell_angle_gamma   120.036
_symmetry_Int_Tables_number   1
_cell_volume   521.974
_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  0.098  0.902  0.750  1.0
  K  K1  1  0.902  0.098  0.250  1.0
  Al  Al2  1  0.812  0.278  0.637  1.0
  Al  Al3  1  0.722  0.188  0.863  1.0
  Al  Al4  1  0.188  0.722  0.363  1.0
  Al  Al5  1  0.278  0.812  0.137  1.0
  Al  Al6  1  0.797  0.584  0.500  1.0
  Al  Al7  1  0.416  0.203  0.000  1.0
  Al  Al8  1  0.203  0.416  0.500  1.0
  Al  Al9  1  0.584  0.797  1.000  1.0
  Si  Si10  1  0.472  0.592  0.638  1.0
  Si  Si11  1  0.408  0.528  0.862  1.0
  Si  Si12  1  0.528  0.408  0.362  1.0
  Si  Si13  1  0.592  0.472  0.138  1.0
  O  O14  1  0.495  0.571  0.555  1.0
  O  O15  1  0.429  0.505  0.945  1.0
  O  O16  1  0.505  0.429  0.445  1.0
  O  O17  1  0.571  0.495  0.055  1.0
  O  O18  1  0.890  0.370  0.552  1.0
  O  O19  1  0.630  0.110  0.948  1.0
  O  O20  1  0.110  0.630  0.448  1.0
  O  O21  1  0.370  0.890  0.052  1.0
  O  O22  1  0.684  0.493  0.667  1.0
  O  O23  1  0.507  0.316  0.833  1.0
  O  O24  1  0.316  0.507  0.333  1.0
  O  O25  1  0.493  0.684  0.167  1.0
  O  O26  1  0.565  0.915  0.654  1.0
  O  O27  1  0.085  0.435  0.846  1.0
  O  O28  1  0.435  0.085  0.346  1.0
  O  O29  1  0.915  0.565  0.154  1.0
  O  O30  1  0.144  0.371  0.666  1.0
  O  O31  1  0.629  0.856  0.834  1.0
  O  O32  1  0.856  0.629  0.334  1.0
  O  O33  1  0.371  0.144  0.166  1.0
  O  O34  1  0.064  0.989  0.527  1.0
  O  O35  1  0.011  0.936  0.973  1.0
  O  O36  1  0.936  0.011  0.473  1.0
  O  O37  1  0.989  0.064  0.027  1.0
[/CIF]
.