The material structure described by Gd2SrAl2O7 crystallizes in the tetragonal I4/mmm space group. Sr(1) is bonded to four equivalent O(3) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(1)O12 cuboctahedra, and faces with eight equivalent Al(1)O6 octahedra. Gd(1) is bonded in a 9-coordinate geometry to four equivalent O(1) and five equivalent O(2) atoms. Al(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form AlO6 octahedra that share corners with five equivalent Al(1)O6 octahedra and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-11°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Gd(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded to five equivalent Gd(1) and one Al(1) atom to form distorted OGd5Al octahedra that share  a cornercorner with one O(3)Sr4Al2 octahedra, corners with four equivalent O(2)Gd5Al octahedra, and edges with eight equivalent O(2)Gd5Al octahedra. The corner-sharing octahedral tilt angles range from 0-19°. In the third O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Al(1) atoms to form distorted OSr4Al2 octahedra that share corners with two equivalent O(2)Gd5Al octahedra, corners with four equivalent O(3)Sr4Al2 octahedra, and edges with four equivalent O(3)Sr4Al2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Al(1) atoms to form distorted OSr4Al2 octahedra that share corners with two equivalent O(2)Gd5Al octahedra, corners with four equivalent O(3)Sr4Al2 octahedra, and edges with four equivalent O(3)Sr4Al2 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_SrGd2Al2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.276
_cell_length_b   10.276
_cell_length_c   10.276
_cell_angle_alpha   159.006
_cell_angle_beta   159.006
_cell_angle_gamma   29.861
_symmetry_Int_Tables_number   1
_cell_volume   139.194
_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
  Sr  Sr0  1  0.500  0.500  0.000  1.0
  Gd  Gd1  1  0.682  0.682  0.000  1.0
  Gd  Gd2  1  0.318  0.318  0.000  1.0
  Al  Al3  1  0.095  0.095  0.000  1.0
  Al  Al4  1  0.905  0.905  0.000  1.0
  O  O5  1  0.396  0.896  0.500  1.0
  O  O6  1  0.896  0.396  0.500  1.0
  O  O7  1  0.604  0.104  0.500  1.0
  O  O8  1  0.104  0.604  0.500  1.0
  O  O9  1  0.796  0.796  0.000  1.0
  O  O10  1  0.204  0.204  0.000  1.0
  O  O11  1  0.000  0.000  0.000  1.0
[/CIF]
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The material structure described by Gd2SrAl2O7 crystallizes in the tetragonal I4/mmm space group. Sr(1) is bonded to four equivalent O(3) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(1)O12 cuboctahedra, and faces with eight equivalent Al(1)O6 octahedra. Gd(1) is bonded in a 9-coordinate geometry to four equivalent O(1) and five equivalent O(2) atoms. Al(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form AlO6 octahedra that share corners with five equivalent Al(1)O6 octahedra and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-11°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Gd(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded to five equivalent Gd(1) and one Al(1) atom to form distorted OGd5Al octahedra that share  a cornercorner with one O(3)Sr4Al2 octahedra, corners with four equivalent O(2)Gd5Al octahedra, and edges with eight equivalent O(2)Gd5Al octahedra. The corner-sharing octahedral tilt angles range from 0-19°. In the third O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Al(1) atoms to form distorted OSr4Al2 octahedra that share corners with two equivalent O(2)Gd5Al octahedra, corners with four equivalent O(3)Sr4Al2 octahedra, and edges with four equivalent O(3)Sr4Al2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Al(1) atoms to form distorted OSr4Al2 octahedra that share corners with two equivalent O(2)Gd5Al octahedra, corners with four equivalent O(3)Sr4Al2 octahedra, and edges with four equivalent O(3)Sr4Al2 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_SrGd2Al2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.276
_cell_length_b   10.276
_cell_length_c   10.276
_cell_angle_alpha   159.006
_cell_angle_beta   159.006
_cell_angle_gamma   29.861
_symmetry_Int_Tables_number   1
_cell_volume   139.194
_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
  Sr  Sr0  1  0.500  0.500  0.000  1.0
  Gd  Gd1  1  0.682  0.682  0.000  1.0
  Gd  Gd2  1  0.318  0.318  0.000  1.0
  Al  Al3  1  0.095  0.095  0.000  1.0
  Al  Al4  1  0.905  0.905  0.000  1.0
  O  O5  1  0.396  0.896  0.500  1.0
  O  O6  1  0.896  0.396  0.500  1.0
  O  O7  1  0.604  0.104  0.500  1.0
  O  O8  1  0.104  0.604  0.500  1.0
  O  O9  1  0.796  0.796  0.000  1.0
  O  O10  1  0.204  0.204  0.000  1.0
  O  O11  1  0.000  0.000  0.000  1.0
[/CIF]
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