The compound described by Al2Si(O2F)2 crystallizes in the orthorhombic Pnma space group. Al(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent F(1) atoms to form AlO4F2 octahedra that share corners with two equivalent Al(1)O4F2 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Al(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 34°. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with eight equivalent Al(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. F(1) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Al2Si(O2F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.708
_cell_length_b   8.497
_cell_length_c   8.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   355.607
_cell_formula_units_Z   4
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
  Al  Al0  1  0.097  0.917  0.130  1.0
  Al  Al1  1  0.597  0.083  0.370  1.0
  Al  Al2  1  0.903  0.417  0.870  1.0
  Al  Al3  1  0.403  0.583  0.630  1.0
  Al  Al4  1  0.597  0.417  0.370  1.0
  Al  Al5  1  0.097  0.583  0.130  1.0
  Al  Al6  1  0.403  0.917  0.630  1.0
  Al  Al7  1  0.903  0.083  0.870  1.0
  Si  Si8  1  0.604  0.750  0.940  1.0
  Si  Si9  1  0.104  0.250  0.560  1.0
  Si  Si10  1  0.396  0.250  0.060  1.0
  Si  Si11  1  0.896  0.750  0.440  1.0
  O  O12  1  0.460  0.250  0.244  1.0
  O  O13  1  0.792  0.593  0.989  1.0
  O  O14  1  0.708  0.907  0.489  1.0
  O  O15  1  0.208  0.093  0.011  1.0
  O  O16  1  0.960  0.750  0.256  1.0
  O  O17  1  0.292  0.407  0.511  1.0
  O  O18  1  0.040  0.250  0.744  1.0
  O  O19  1  0.540  0.750  0.756  1.0
  O  O20  1  0.708  0.593  0.489  1.0
  O  O21  1  0.208  0.407  0.011  1.0
  O  O22  1  0.292  0.093  0.511  1.0
  O  O23  1  0.792  0.907  0.989  1.0
  O  O24  1  0.201  0.750  0.533  1.0
  O  O25  1  0.701  0.250  0.967  1.0
  O  O26  1  0.799  0.250  0.467  1.0
  O  O27  1  0.299  0.750  0.033  1.0
  F  F28  1  0.099  0.944  0.752  1.0
  F  F29  1  0.599  0.056  0.748  1.0
  F  F30  1  0.599  0.444  0.748  1.0
  F  F31  1  0.401  0.556  0.252  1.0
  F  F32  1  0.901  0.056  0.248  1.0
  F  F33  1  0.401  0.944  0.252  1.0
  F  F34  1  0.099  0.556  0.752  1.0
  F  F35  1  0.901  0.444  0.248  1.0
[/CIF]
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The compound described by Al2Si(O2F)2 crystallizes in the orthorhombic Pnma space group. Al(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent F(1) atoms to form AlO4F2 octahedra that share corners with two equivalent Al(1)O4F2 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Al(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 34°. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with eight equivalent Al(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Si(1) atom. F(1) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Al2Si(O2F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.708
_cell_length_b   8.497
_cell_length_c   8.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   355.607
_cell_formula_units_Z   4
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
  Al  Al0  1  0.097  0.917  0.130  1.0
  Al  Al1  1  0.597  0.083  0.370  1.0
  Al  Al2  1  0.903  0.417  0.870  1.0
  Al  Al3  1  0.403  0.583  0.630  1.0
  Al  Al4  1  0.597  0.417  0.370  1.0
  Al  Al5  1  0.097  0.583  0.130  1.0
  Al  Al6  1  0.403  0.917  0.630  1.0
  Al  Al7  1  0.903  0.083  0.870  1.0
  Si  Si8  1  0.604  0.750  0.940  1.0
  Si  Si9  1  0.104  0.250  0.560  1.0
  Si  Si10  1  0.396  0.250  0.060  1.0
  Si  Si11  1  0.896  0.750  0.440  1.0
  O  O12  1  0.460  0.250  0.244  1.0
  O  O13  1  0.792  0.593  0.989  1.0
  O  O14  1  0.708  0.907  0.489  1.0
  O  O15  1  0.208  0.093  0.011  1.0
  O  O16  1  0.960  0.750  0.256  1.0
  O  O17  1  0.292  0.407  0.511  1.0
  O  O18  1  0.040  0.250  0.744  1.0
  O  O19  1  0.540  0.750  0.756  1.0
  O  O20  1  0.708  0.593  0.489  1.0
  O  O21  1  0.208  0.407  0.011  1.0
  O  O22  1  0.292  0.093  0.511  1.0
  O  O23  1  0.792  0.907  0.989  1.0
  O  O24  1  0.201  0.750  0.533  1.0
  O  O25  1  0.701  0.250  0.967  1.0
  O  O26  1  0.799  0.250  0.467  1.0
  O  O27  1  0.299  0.750  0.033  1.0
  F  F28  1  0.099  0.944  0.752  1.0
  F  F29  1  0.599  0.056  0.748  1.0
  F  F30  1  0.599  0.444  0.748  1.0
  F  F31  1  0.401  0.556  0.252  1.0
  F  F32  1  0.901  0.056  0.248  1.0
  F  F33  1  0.401  0.944  0.252  1.0
  F  F34  1  0.099  0.556  0.752  1.0
  F  F35  1  0.901  0.444  0.248  1.0
[/CIF]
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