The material described by AlSi3O8 is Low Tridymite-derived structured and crystallizes in the monoclinic Pc space group. Al(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlSi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.043
_cell_length_b   8.878
_cell_length_c   12.378
_cell_angle_alpha   46.443
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.630
_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
  Al  Al0  1  0.649  0.652  0.666  1.0
  Al  Al1  1  0.351  0.652  0.166  1.0
  Si  Si2  1  0.861  0.990  0.328  1.0
  Si  Si3  1  0.151  0.339  0.838  1.0
  Si  Si4  1  0.368  0.016  0.169  1.0
  Si  Si5  1  0.849  0.339  0.338  1.0
  Si  Si6  1  0.632  0.016  0.669  1.0
  Si  Si7  1  0.139  0.990  0.828  1.0
  O  O8  1  0.377  0.493  0.715  1.0
  O  O9  1  0.140  0.943  0.290  1.0
  O  O10  1  0.898  0.482  0.795  1.0
  O  O11  1  0.638  0.085  0.199  1.0
  O  O12  1  0.102  0.482  0.295  1.0
  O  O13  1  0.362  0.085  0.699  1.0
  O  O14  1  0.623  0.493  0.215  1.0
  O  O15  1  0.860  0.943  0.790  1.0
  O  O16  1  0.751  0.780  0.486  1.0
  O  O17  1  0.255  0.221  0.005  1.0
  O  O18  1  0.745  0.221  0.505  1.0
  O  O19  1  0.249  0.780  0.986  1.0
  O  O20  1  0.568  0.832  0.676  1.0
  O  O21  1  0.927  0.166  0.333  1.0
  O  O22  1  0.073  0.166  0.833  1.0
  O  O23  1  0.432  0.832  0.176  1.0
[/CIF]
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The material described by AlSi3O8 is Low Tridymite-derived structured and crystallizes in the monoclinic Pc space group. Al(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlSi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.043
_cell_length_b   8.878
_cell_length_c   12.378
_cell_angle_alpha   46.443
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.630
_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
  Al  Al0  1  0.649  0.652  0.666  1.0
  Al  Al1  1  0.351  0.652  0.166  1.0
  Si  Si2  1  0.861  0.990  0.328  1.0
  Si  Si3  1  0.151  0.339  0.838  1.0
  Si  Si4  1  0.368  0.016  0.169  1.0
  Si  Si5  1  0.849  0.339  0.338  1.0
  Si  Si6  1  0.632  0.016  0.669  1.0
  Si  Si7  1  0.139  0.990  0.828  1.0
  O  O8  1  0.377  0.493  0.715  1.0
  O  O9  1  0.140  0.943  0.290  1.0
  O  O10  1  0.898  0.482  0.795  1.0
  O  O11  1  0.638  0.085  0.199  1.0
  O  O12  1  0.102  0.482  0.295  1.0
  O  O13  1  0.362  0.085  0.699  1.0
  O  O14  1  0.623  0.493  0.215  1.0
  O  O15  1  0.860  0.943  0.790  1.0
  O  O16  1  0.751  0.780  0.486  1.0
  O  O17  1  0.255  0.221  0.005  1.0
  O  O18  1  0.745  0.221  0.505  1.0
  O  O19  1  0.249  0.780  0.986  1.0
  O  O20  1  0.568  0.832  0.676  1.0
  O  O21  1  0.927  0.166  0.333  1.0
  O  O22  1  0.073  0.166  0.833  1.0
  O  O23  1  0.432  0.832  0.176  1.0
[/CIF]
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