The compound described by CaYAl3O7 crystallizes in the orthorhombic Cmm2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(4), one O(6), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(3), one O(6), and two equivalent O(1) atoms to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ca(1) and two equivalent Al(3) atoms to form distorted OCa2Al2 tetrahedra that share corners with two equivalent O(4)Ca2YAl tetrahedra, corners with two equivalent O(3)CaY2Al tetrahedra, and edges with two equivalent O(4)Ca2YAl tetrahedra. In the second O site, O(6) is bonded to two equivalent Y(1) and two equivalent Al(2) atoms to form distorted OY2Al2 tetrahedra that share corners with two equivalent O(4)Ca2YAl tetrahedra, corners with two equivalent O(3)CaY2Al tetrahedra, and edges with two equivalent O(3)CaY2Al tetrahedra. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(2) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(3) atom. In the fifth O site, O(3) is bonded to one Ca(1), two equivalent Y(1), and one Al(2) atom to form distorted OCaY2Al tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Y2Al2 tetrahedra, corners with four equivalent O(4)Ca2YAl tetrahedra,  an edgeedge with one O(3)CaY2Al tetrahedra, and  an edgeedge with one O(6)Y2Al2 tetrahedra. In the sixth O site, O(4) is bonded to two equivalent Ca(1), one Y(1), and one Al(3) atom to form distorted OCa2YAl tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Y2Al2 tetrahedra, corners with four equivalent O(3)CaY2Al tetrahedra,  an edgeedge with one O(5)Ca2Al2 tetrahedra, and  an edgeedge with one O(4)Ca2YAl tetrahedra. is represented by the CIF card [CIF]
data_CaYAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.759
_cell_length_b   7.759
_cell_length_c   5.098
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.170
_symmetry_Int_Tables_number   1
_cell_volume   306.917
_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
  Ca  Ca0  1  0.339  0.661  0.515  1.0
  Ca  Ca1  1  0.661  0.339  0.515  1.0
  Y  Y2  1  0.162  0.162  0.485  1.0
  Y  Y3  1  0.838  0.838  0.485  1.0
  Al  Al4  1  0.500  0.000  0.001  1.0
  Al  Al5  1  0.000  0.500  0.001  1.0
  Al  Al6  1  0.143  0.857  0.956  1.0
  Al  Al7  1  0.354  0.354  0.044  1.0
  Al  Al8  1  0.857  0.143  0.956  1.0
  Al  Al9  1  0.646  0.646  0.044  1.0
  O  O10  1  0.337  0.913  0.799  1.0
  O  O11  1  0.156  0.402  0.205  1.0
  O  O12  1  0.663  0.087  0.799  1.0
  O  O13  1  0.844  0.598  0.205  1.0
  O  O14  1  0.598  0.844  0.205  1.0
  O  O15  1  0.913  0.337  0.799  1.0
  O  O16  1  0.402  0.156  0.205  1.0
  O  O17  1  0.087  0.663  0.799  1.0
  O  O18  1  0.131  0.869  0.299  1.0
  O  O19  1  0.347  0.347  0.703  1.0
  O  O20  1  0.869  0.131  0.299  1.0
  O  O21  1  0.653  0.653  0.703  1.0
  O  O22  1  0.500  0.500  0.183  1.0
  O  O23  1  0.000  0.000  0.795  1.0
[/CIF]
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The compound described by CaYAl3O7 crystallizes in the orthorhombic Cmm2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(4), one O(6), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(3), one O(6), and two equivalent O(1) atoms to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form corner-sharing AlO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to two equivalent Ca(1) and two equivalent Al(3) atoms to form distorted OCa2Al2 tetrahedra that share corners with two equivalent O(4)Ca2YAl tetrahedra, corners with two equivalent O(3)CaY2Al tetrahedra, and edges with two equivalent O(4)Ca2YAl tetrahedra. In the second O site, O(6) is bonded to two equivalent Y(1) and two equivalent Al(2) atoms to form distorted OY2Al2 tetrahedra that share corners with two equivalent O(4)Ca2YAl tetrahedra, corners with two equivalent O(3)CaY2Al tetrahedra, and edges with two equivalent O(3)CaY2Al tetrahedra. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(2) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(3) atom. In the fifth O site, O(3) is bonded to one Ca(1), two equivalent Y(1), and one Al(2) atom to form distorted OCaY2Al tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Y2Al2 tetrahedra, corners with four equivalent O(4)Ca2YAl tetrahedra,  an edgeedge with one O(3)CaY2Al tetrahedra, and  an edgeedge with one O(6)Y2Al2 tetrahedra. In the sixth O site, O(4) is bonded to two equivalent Ca(1), one Y(1), and one Al(3) atom to form distorted OCa2YAl tetrahedra that share  a cornercorner with one O(5)Ca2Al2 tetrahedra,  a cornercorner with one O(6)Y2Al2 tetrahedra, corners with four equivalent O(3)CaY2Al tetrahedra,  an edgeedge with one O(5)Ca2Al2 tetrahedra, and  an edgeedge with one O(4)Ca2YAl tetrahedra. is represented by the CIF card [CIF]
data_CaYAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.759
_cell_length_b   7.759
_cell_length_c   5.098
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.170
_symmetry_Int_Tables_number   1
_cell_volume   306.917
_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
  Ca  Ca0  1  0.339  0.661  0.515  1.0
  Ca  Ca1  1  0.661  0.339  0.515  1.0
  Y  Y2  1  0.162  0.162  0.485  1.0
  Y  Y3  1  0.838  0.838  0.485  1.0
  Al  Al4  1  0.500  0.000  0.001  1.0
  Al  Al5  1  0.000  0.500  0.001  1.0
  Al  Al6  1  0.143  0.857  0.956  1.0
  Al  Al7  1  0.354  0.354  0.044  1.0
  Al  Al8  1  0.857  0.143  0.956  1.0
  Al  Al9  1  0.646  0.646  0.044  1.0
  O  O10  1  0.337  0.913  0.799  1.0
  O  O11  1  0.156  0.402  0.205  1.0
  O  O12  1  0.663  0.087  0.799  1.0
  O  O13  1  0.844  0.598  0.205  1.0
  O  O14  1  0.598  0.844  0.205  1.0
  O  O15  1  0.913  0.337  0.799  1.0
  O  O16  1  0.402  0.156  0.205  1.0
  O  O17  1  0.087  0.663  0.799  1.0
  O  O18  1  0.131  0.869  0.299  1.0
  O  O19  1  0.347  0.347  0.703  1.0
  O  O20  1  0.869  0.131  0.299  1.0
  O  O21  1  0.653  0.653  0.703  1.0
  O  O22  1  0.500  0.500  0.183  1.0
  O  O23  1  0.000  0.000  0.795  1.0
[/CIF]
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