The compound described by CaYAl3O7 crystallizes in the monoclinic P2_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(6), one O(7), two equivalent O(1), and two equivalent O(4) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(6), one O(7), two equivalent O(2), and two equivalent O(5) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), one Y(1), and one Al(1) atom to form distorted OCa2YAl tetrahedra that share corners with two equivalent O(1)Ca2YAl tetrahedra, corners with two equivalent O(3)CaYAl2 tetrahedra, and  an edgeedge with one O(3)CaYAl2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Y(1), and one Al(2) atom. In the third O site, O(3) is bonded to one Ca(1), one Y(1), one Al(1), and one Al(2) atom to form a mixture of distorted corner and edge-sharing OCaYAl2 tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Al(1), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Y(1), one Al(2), and one Al(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ca(1), one Y(1), one Al(2), and one Al(3) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(3) atom. is represented by the CIF file [CIF]
data_CaYAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.744
_cell_length_b   5.106
_cell_length_c   7.786
_cell_angle_alpha   89.875
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   307.843
_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  0.161  0.515  0.418  1.0
  Ca  Ca1  1  0.661  0.485  0.582  1.0
  Y  Y2  1  0.840  0.520  0.095  1.0
  Y  Y3  1  0.340  0.480  0.905  1.0
  Al  Al4  1  0.355  0.956  0.611  1.0
  Al  Al5  1  0.855  0.044  0.389  1.0
  Al  Al6  1  0.643  0.958  0.899  1.0
  Al  Al7  1  0.143  0.042  0.101  1.0
  Al  Al8  1  0.501  0.002  0.248  1.0
  Al  Al9  1  0.001  0.998  0.752  1.0
  O  O10  1  0.359  0.297  0.629  1.0
  O  O11  1  0.859  0.703  0.371  1.0
  O  O12  1  0.640  0.301  0.908  1.0
  O  O13  1  0.140  0.699  0.092  1.0
  O  O14  1  0.001  0.196  0.245  1.0
  O  O15  1  0.501  0.804  0.755  1.0
  O  O16  1  0.402  0.815  0.410  1.0
  O  O17  1  0.902  0.185  0.590  1.0
  O  O18  1  0.592  0.789  0.093  1.0
  O  O19  1  0.092  0.211  0.907  1.0
  O  O20  1  0.344  0.195  0.142  1.0
  O  O21  1  0.844  0.805  0.858  1.0
  O  O22  1  0.662  0.208  0.331  1.0
  O  O23  1  0.162  0.792  0.669  1.0
[/CIF]
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The compound described by CaYAl3O7 crystallizes in the monoclinic P2_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(6), one O(7), two equivalent O(1), and two equivalent O(4) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(6), one O(7), two equivalent O(2), and two equivalent O(5) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), one Y(1), and one Al(1) atom to form distorted OCa2YAl tetrahedra that share corners with two equivalent O(1)Ca2YAl tetrahedra, corners with two equivalent O(3)CaYAl2 tetrahedra, and  an edgeedge with one O(3)CaYAl2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Y(1), and one Al(2) atom. In the third O site, O(3) is bonded to one Ca(1), one Y(1), one Al(1), and one Al(2) atom to form a mixture of distorted corner and edge-sharing OCaYAl2 tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Al(1), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Y(1), one Al(2), and one Al(3) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ca(1), one Y(1), one Al(2), and one Al(3) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(1), one Y(1), one Al(1), and one Al(3) atom. is represented by the CIF file [CIF]
data_CaYAl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.744
_cell_length_b   5.106
_cell_length_c   7.786
_cell_angle_alpha   89.875
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   307.843
_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  0.161  0.515  0.418  1.0
  Ca  Ca1  1  0.661  0.485  0.582  1.0
  Y  Y2  1  0.840  0.520  0.095  1.0
  Y  Y3  1  0.340  0.480  0.905  1.0
  Al  Al4  1  0.355  0.956  0.611  1.0
  Al  Al5  1  0.855  0.044  0.389  1.0
  Al  Al6  1  0.643  0.958  0.899  1.0
  Al  Al7  1  0.143  0.042  0.101  1.0
  Al  Al8  1  0.501  0.002  0.248  1.0
  Al  Al9  1  0.001  0.998  0.752  1.0
  O  O10  1  0.359  0.297  0.629  1.0
  O  O11  1  0.859  0.703  0.371  1.0
  O  O12  1  0.640  0.301  0.908  1.0
  O  O13  1  0.140  0.699  0.092  1.0
  O  O14  1  0.001  0.196  0.245  1.0
  O  O15  1  0.501  0.804  0.755  1.0
  O  O16  1  0.402  0.815  0.410  1.0
  O  O17  1  0.902  0.185  0.590  1.0
  O  O18  1  0.592  0.789  0.093  1.0
  O  O19  1  0.092  0.211  0.907  1.0
  O  O20  1  0.344  0.195  0.142  1.0
  O  O21  1  0.844  0.805  0.858  1.0
  O  O22  1  0.662  0.208  0.331  1.0
  O  O23  1  0.162  0.792  0.669  1.0
[/CIF]
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