The structure described by YAl3O6 crystallizes in the monoclinic C2/c space group. Y(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted YO6 pentagonal pyramids that share corners with four equivalent Al(1)O4 tetrahedra, edges with two equivalent Al(1)O4 tetrahedra, and edges with two equivalent Al(2)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share corners with two equivalent Y(1)O6 pentagonal pyramids, corners with two equivalent Al(1)O4 tetrahedra, corners with two equivalent Al(2)O4 tetrahedra, and  an edgeedge with one Y(1)O6 pentagonal pyramid. In the second Al site, Al(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted AlO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra and edges with two equivalent Y(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Y(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Y(1), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Y(1), one Al(1), and one Al(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_YAl3O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.273
_cell_length_b   7.273
_cell_length_c   5.888
_cell_angle_alpha   67.406
_cell_angle_beta   67.406
_cell_angle_gamma   79.325
_symmetry_Int_Tables_number   1
_cell_volume   265.180
_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
  Y  Y0  1  0.261  0.739  0.750  1.0
  Y  Y1  1  0.739  0.261  0.250  1.0
  Al  Al2  1  0.208  0.357  0.245  1.0
  Al  Al3  1  0.827  0.173  0.750  1.0
  Al  Al4  1  0.357  0.208  0.745  1.0
  Al  Al5  1  0.643  0.792  0.255  1.0
  Al  Al6  1  0.173  0.827  0.250  1.0
  Al  Al7  1  0.792  0.643  0.755  1.0
  O  O8  1  0.388  0.275  0.404  1.0
  O  O9  1  0.844  0.387  0.808  1.0
  O  O10  1  0.788  0.007  0.080  1.0
  O  O11  1  0.275  0.388  0.904  1.0
  O  O12  1  0.993  0.212  0.420  1.0
  O  O13  1  0.613  0.156  0.692  1.0
  O  O14  1  0.387  0.844  0.308  1.0
  O  O15  1  0.007  0.788  0.580  1.0
  O  O16  1  0.725  0.612  0.096  1.0
  O  O17  1  0.212  0.993  0.920  1.0
  O  O18  1  0.156  0.613  0.192  1.0
  O  O19  1  0.612  0.725  0.596  1.0
[/CIF]
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The structure described by YAl3O6 crystallizes in the monoclinic C2/c space group. Y(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted YO6 pentagonal pyramids that share corners with four equivalent Al(1)O4 tetrahedra, edges with two equivalent Al(1)O4 tetrahedra, and edges with two equivalent Al(2)O4 tetrahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share corners with two equivalent Y(1)O6 pentagonal pyramids, corners with two equivalent Al(1)O4 tetrahedra, corners with two equivalent Al(2)O4 tetrahedra, and  an edgeedge with one Y(1)O6 pentagonal pyramid. In the second Al site, Al(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form distorted AlO4 tetrahedra that share corners with four equivalent Al(1)O4 tetrahedra and edges with two equivalent Y(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Y(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Y(1), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Y(1), one Al(1), and one Al(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_YAl3O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.273
_cell_length_b   7.273
_cell_length_c   5.888
_cell_angle_alpha   67.406
_cell_angle_beta   67.406
_cell_angle_gamma   79.325
_symmetry_Int_Tables_number   1
_cell_volume   265.180
_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
  Y  Y0  1  0.261  0.739  0.750  1.0
  Y  Y1  1  0.739  0.261  0.250  1.0
  Al  Al2  1  0.208  0.357  0.245  1.0
  Al  Al3  1  0.827  0.173  0.750  1.0
  Al  Al4  1  0.357  0.208  0.745  1.0
  Al  Al5  1  0.643  0.792  0.255  1.0
  Al  Al6  1  0.173  0.827  0.250  1.0
  Al  Al7  1  0.792  0.643  0.755  1.0
  O  O8  1  0.388  0.275  0.404  1.0
  O  O9  1  0.844  0.387  0.808  1.0
  O  O10  1  0.788  0.007  0.080  1.0
  O  O11  1  0.275  0.388  0.904  1.0
  O  O12  1  0.993  0.212  0.420  1.0
  O  O13  1  0.613  0.156  0.692  1.0
  O  O14  1  0.387  0.844  0.308  1.0
  O  O15  1  0.007  0.788  0.580  1.0
  O  O16  1  0.725  0.612  0.096  1.0
  O  O17  1  0.212  0.993  0.920  1.0
  O  O18  1  0.156  0.613  0.192  1.0
  O  O19  1  0.612  0.725  0.596  1.0
[/CIF]
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