The compound described by CaGdAlO4 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. Ca(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. Gd(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. Al(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form corner-sharing AlO6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), four equivalent Gd(1), and one Al(1) atom to form distorted OCaGd4Al octahedra that share  a cornercorner with one O(2)Ca4GdAl octahedra, corners with four equivalent O(1)CaGd4Al octahedra, corners with twelve equivalent O(3)Ca2Gd2Al2 octahedra, edges with four equivalent O(2)Ca4GdAl octahedra, edges with four equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the second O site, O(2) is bonded to four equivalent Ca(1), one Gd(1), and one Al(1) atom to form distorted OCa4GdAl octahedra that share  a cornercorner with one O(1)CaGd4Al octahedra, corners with four equivalent O(2)Ca4GdAl octahedra, corners with twelve equivalent O(3)Ca2Gd2Al2 octahedra, edges with four equivalent O(2)Ca4GdAl octahedra, edges with four equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Gd(1), and two equivalent Al(1) atoms to form distorted OCa2Gd2Al2 octahedra that share corners with two equivalent O(3)Ca2Gd2Al2 octahedra, corners with six equivalent O(2)Ca4GdAl octahedra, corners with six equivalent O(1)CaGd4Al octahedra, edges with two equivalent O(3)Ca2Gd2Al2 octahedra, faces with two equivalent O(2)Ca4GdAl octahedra, faces with two equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 7-54°. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaGdAlO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.529
_cell_length_b   6.529
_cell_length_c   6.529
_cell_angle_alpha   147.126
_cell_angle_beta   147.126
_cell_angle_gamma   47.178
_symmetry_Int_Tables_number   1
_cell_volume   81.692
_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
  Ca  Ca0  1  0.643  0.643  0.000  1.0
  Gd  Gd1  1  0.358  0.358  0.000  1.0
  Al  Al2  1  0.006  0.006  0.000  1.0
  O  O3  1  0.833  0.833  0.000  1.0
  O  O4  1  0.169  0.169  0.000  1.0
  O  O5  1  0.496  0.996  0.500  1.0
  O  O6  1  0.996  0.496  0.500  1.0
[/CIF]
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The compound described by CaGdAlO4 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4mm space group. Ca(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. Gd(1) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. Al(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form corner-sharing AlO6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), four equivalent Gd(1), and one Al(1) atom to form distorted OCaGd4Al octahedra that share  a cornercorner with one O(2)Ca4GdAl octahedra, corners with four equivalent O(1)CaGd4Al octahedra, corners with twelve equivalent O(3)Ca2Gd2Al2 octahedra, edges with four equivalent O(2)Ca4GdAl octahedra, edges with four equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 0-53°. In the second O site, O(2) is bonded to four equivalent Ca(1), one Gd(1), and one Al(1) atom to form distorted OCa4GdAl octahedra that share  a cornercorner with one O(1)CaGd4Al octahedra, corners with four equivalent O(2)Ca4GdAl octahedra, corners with twelve equivalent O(3)Ca2Gd2Al2 octahedra, edges with four equivalent O(2)Ca4GdAl octahedra, edges with four equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 0-54°. In the third O site, O(3) is bonded to two equivalent Ca(1), two equivalent Gd(1), and two equivalent Al(1) atoms to form distorted OCa2Gd2Al2 octahedra that share corners with two equivalent O(3)Ca2Gd2Al2 octahedra, corners with six equivalent O(2)Ca4GdAl octahedra, corners with six equivalent O(1)CaGd4Al octahedra, edges with two equivalent O(3)Ca2Gd2Al2 octahedra, faces with two equivalent O(2)Ca4GdAl octahedra, faces with two equivalent O(1)CaGd4Al octahedra, and faces with four equivalent O(3)Ca2Gd2Al2 octahedra. The corner-sharing octahedral tilt angles range from 7-54°. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaGdAlO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.529
_cell_length_b   6.529
_cell_length_c   6.529
_cell_angle_alpha   147.126
_cell_angle_beta   147.126
_cell_angle_gamma   47.178
_symmetry_Int_Tables_number   1
_cell_volume   81.692
_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
  Ca  Ca0  1  0.643  0.643  0.000  1.0
  Gd  Gd1  1  0.358  0.358  0.000  1.0
  Al  Al2  1  0.006  0.006  0.000  1.0
  O  O3  1  0.833  0.833  0.000  1.0
  O  O4  1  0.169  0.169  0.000  1.0
  O  O5  1  0.496  0.996  0.500  1.0
  O  O6  1  0.996  0.496  0.500  1.0
[/CIF]
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