The material described by Al(Si2O5)2 is Low Tridymite-derived structured and crystallizes in the monoclinic C2 space group. Al(1) is bonded to two equivalent O(4) and two equivalent O(5) atoms to form AlO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)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(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(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(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Al(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al(Si2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.654
_cell_length_b   7.654
_cell_length_c   5.046
_cell_angle_alpha   88.272
_cell_angle_beta   88.272
_cell_angle_gamma   47.663
_symmetry_Int_Tables_number   1
_cell_volume   218.366
_cell_formula_units_Z   1
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  0.492  0.508  0.000  1.0
  Si  Si1  1  0.703  0.015  0.759  1.0
  Si  Si2  1  0.293  0.013  0.727  1.0
  Si  Si3  1  0.987  0.707  0.273  1.0
  Si  Si4  1  0.985  0.297  0.241  1.0
  O  O5  1  0.489  0.034  0.662  1.0
  O  O6  1  0.966  0.511  0.338  1.0
  O  O7  1  0.921  0.851  0.547  1.0
  O  O8  1  0.109  0.214  0.947  1.0
  O  O9  1  0.613  0.275  0.780  1.0
  O  O10  1  0.413  0.754  0.832  1.0
  O  O11  1  0.786  0.891  0.053  1.0
  O  O12  1  0.149  0.079  0.453  1.0
  O  O13  1  0.246  0.587  0.168  1.0
  O  O14  1  0.725  0.387  0.220  1.0
[/CIF]
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The material described by Al(Si2O5)2 is Low Tridymite-derived structured and crystallizes in the monoclinic C2 space group. Al(1) is bonded to two equivalent O(4) and two equivalent O(5) atoms to form AlO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)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(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(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(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Al(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Al(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al(Si2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.654
_cell_length_b   7.654
_cell_length_c   5.046
_cell_angle_alpha   88.272
_cell_angle_beta   88.272
_cell_angle_gamma   47.663
_symmetry_Int_Tables_number   1
_cell_volume   218.366
_cell_formula_units_Z   1
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  0.492  0.508  0.000  1.0
  Si  Si1  1  0.703  0.015  0.759  1.0
  Si  Si2  1  0.293  0.013  0.727  1.0
  Si  Si3  1  0.987  0.707  0.273  1.0
  Si  Si4  1  0.985  0.297  0.241  1.0
  O  O5  1  0.489  0.034  0.662  1.0
  O  O6  1  0.966  0.511  0.338  1.0
  O  O7  1  0.921  0.851  0.547  1.0
  O  O8  1  0.109  0.214  0.947  1.0
  O  O9  1  0.613  0.275  0.780  1.0
  O  O10  1  0.413  0.754  0.832  1.0
  O  O11  1  0.786  0.891  0.053  1.0
  O  O12  1  0.149  0.079  0.453  1.0
  O  O13  1  0.246  0.587  0.168  1.0
  O  O14  1  0.725  0.387  0.220  1.0
[/CIF]
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