The material structure described by KAl2(SiO3)4 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(4), and four equivalent O(5) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form AlO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with three equivalent Al(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra and corners with three equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-59°. In the second Si site, Si(2) 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 two equivalent Al(1)O6 octahedra and corners with three equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-59°. There are six inequivalent O sites. In the first O site, O(2) is bonded in a water-like geometry to two equivalent Al(1) atoms. In the second O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(1), and one Si(2) atom. In the third O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Si(1), and one Si(2) atom. In the fourth O site, O(5) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Si(1), and one Si(2) atom. In the fifth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the sixth O site, O(1) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAl2(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.221
_cell_length_b   5.221
_cell_length_c   20.153
_cell_angle_alpha   87.406
_cell_angle_beta   87.406
_cell_angle_gamma   120.206
_symmetry_Int_Tables_number   1
_cell_volume   472.832
_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  0.900  0.100  0.750  1.0
  K  K1  1  0.100  0.900  0.250  1.0
  Al  Al2  1  0.675  0.838  0.500  1.0
  Al  Al3  1  0.325  0.162  0.500  1.0
  Al  Al4  1  0.162  0.325  1.000  1.0
  Al  Al5  1  0.838  0.675  0.000  1.0
  Si  Si6  1  0.535  0.394  0.867  1.0
  Si  Si7  1  0.465  0.606  0.133  1.0
  Si  Si8  1  0.606  0.465  0.633  1.0
  Si  Si9  1  0.394  0.535  0.367  1.0
  Si  Si10  1  0.291  0.807  0.633  1.0
  Si  Si11  1  0.709  0.193  0.367  1.0
  Si  Si12  1  0.193  0.709  0.867  1.0
  Si  Si13  1  0.807  0.291  0.133  1.0
  O  O14  1  0.374  0.864  0.553  1.0
  O  O15  1  0.626  0.136  0.447  1.0
  O  O16  1  0.136  0.626  0.947  1.0
  O  O17  1  0.864  0.374  0.053  1.0
  O  O18  1  0.923  0.017  0.951  1.0
  O  O19  1  0.077  0.983  0.049  1.0
  O  O20  1  0.983  0.077  0.549  1.0
  O  O21  1  0.017  0.923  0.451  1.0
  O  O22  1  0.418  0.061  0.842  1.0
  O  O23  1  0.582  0.939  0.158  1.0
  O  O24  1  0.939  0.582  0.658  1.0
  O  O25  1  0.061  0.418  0.342  1.0
  O  O26  1  0.397  0.121  0.668  1.0
  O  O27  1  0.603  0.879  0.332  1.0
  O  O28  1  0.879  0.603  0.832  1.0
  O  O29  1  0.121  0.397  0.168  1.0
  O  O30  1  0.474  0.660  0.668  1.0
  O  O31  1  0.526  0.340  0.332  1.0
  O  O32  1  0.340  0.526  0.832  1.0
  O  O33  1  0.660  0.474  0.168  1.0
  O  O34  1  0.530  0.414  0.947  1.0
  O  O35  1  0.470  0.586  0.053  1.0
  O  O36  1  0.586  0.470  0.553  1.0
  O  O37  1  0.414  0.530  0.447  1.0
[/CIF]
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The material structure described by KAl2(SiO3)4 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(4), and four equivalent O(5) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form AlO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with three equivalent Al(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Al(1)O6 octahedra and corners with three equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-59°. In the second Si site, Si(2) 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 two equivalent Al(1)O6 octahedra and corners with three equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-59°. There are six inequivalent O sites. In the first O site, O(2) is bonded in a water-like geometry to two equivalent Al(1) atoms. In the second O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(1), and one Si(2) atom. In the third O site, O(4) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Si(1), and one Si(2) atom. In the fourth O site, O(5) is bonded in a distorted bent 120 degrees geometry to two equivalent K(1), one Si(1), and one Si(2) atom. In the fifth O site, O(6) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the sixth O site, O(1) is bonded in a trigonal planar geometry to two equivalent Al(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KAl2(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.221
_cell_length_b   5.221
_cell_length_c   20.153
_cell_angle_alpha   87.406
_cell_angle_beta   87.406
_cell_angle_gamma   120.206
_symmetry_Int_Tables_number   1
_cell_volume   472.832
_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  0.900  0.100  0.750  1.0
  K  K1  1  0.100  0.900  0.250  1.0
  Al  Al2  1  0.675  0.838  0.500  1.0
  Al  Al3  1  0.325  0.162  0.500  1.0
  Al  Al4  1  0.162  0.325  1.000  1.0
  Al  Al5  1  0.838  0.675  0.000  1.0
  Si  Si6  1  0.535  0.394  0.867  1.0
  Si  Si7  1  0.465  0.606  0.133  1.0
  Si  Si8  1  0.606  0.465  0.633  1.0
  Si  Si9  1  0.394  0.535  0.367  1.0
  Si  Si10  1  0.291  0.807  0.633  1.0
  Si  Si11  1  0.709  0.193  0.367  1.0
  Si  Si12  1  0.193  0.709  0.867  1.0
  Si  Si13  1  0.807  0.291  0.133  1.0
  O  O14  1  0.374  0.864  0.553  1.0
  O  O15  1  0.626  0.136  0.447  1.0
  O  O16  1  0.136  0.626  0.947  1.0
  O  O17  1  0.864  0.374  0.053  1.0
  O  O18  1  0.923  0.017  0.951  1.0
  O  O19  1  0.077  0.983  0.049  1.0
  O  O20  1  0.983  0.077  0.549  1.0
  O  O21  1  0.017  0.923  0.451  1.0
  O  O22  1  0.418  0.061  0.842  1.0
  O  O23  1  0.582  0.939  0.158  1.0
  O  O24  1  0.939  0.582  0.658  1.0
  O  O25  1  0.061  0.418  0.342  1.0
  O  O26  1  0.397  0.121  0.668  1.0
  O  O27  1  0.603  0.879  0.332  1.0
  O  O28  1  0.879  0.603  0.832  1.0
  O  O29  1  0.121  0.397  0.168  1.0
  O  O30  1  0.474  0.660  0.668  1.0
  O  O31  1  0.526  0.340  0.332  1.0
  O  O32  1  0.340  0.526  0.832  1.0
  O  O33  1  0.660  0.474  0.168  1.0
  O  O34  1  0.530  0.414  0.947  1.0
  O  O35  1  0.470  0.586  0.053  1.0
  O  O36  1  0.586  0.470  0.553  1.0
  O  O37  1  0.414  0.530  0.447  1.0
[/CIF]
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