The compound described by Eu2Al3O8 crystallizes in the cubic I-43m space group. Eu(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form EuO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with three equivalent Eu(1)O6 octahedra. Al(1) is bonded to four equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Eu(1)O6 octahedra and corners with four equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Eu(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Eu(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Eu2Al3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.786
_cell_length_b   7.786
_cell_length_c   7.786
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   363.341
_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
  Eu  Eu0  1  0.297  0.297  0.297  1.0
  Eu  Eu1  1  0.703  0.000  0.000  1.0
  Eu  Eu2  1  0.000  0.703  0.000  1.0
  Eu  Eu3  1  0.000  0.000  0.703  1.0
  Al  Al4  1  0.250  0.750  0.500  1.0
  Al  Al5  1  0.750  0.250  0.500  1.0
  Al  Al6  1  0.750  0.500  0.250  1.0
  Al  Al7  1  0.250  0.500  0.750  1.0
  Al  Al8  1  0.500  0.250  0.750  1.0
  Al  Al9  1  0.500  0.750  0.250  1.0
  O  O10  1  0.790  0.790  0.790  1.0
  O  O11  1  0.210  0.000  0.000  1.0
  O  O12  1  0.000  0.210  0.000  1.0
  O  O13  1  0.000  0.000  0.210  1.0
  O  O14  1  0.278  0.553  0.553  1.0
  O  O15  1  0.722  0.276  0.276  1.0
  O  O16  1  0.000  0.447  0.724  1.0
  O  O17  1  0.553  0.553  0.278  1.0
  O  O18  1  0.000  0.724  0.447  1.0
  O  O19  1  0.276  0.276  0.722  1.0
  O  O20  1  0.447  0.724  0.000  1.0
  O  O21  1  0.724  0.447  0.000  1.0
  O  O22  1  0.553  0.278  0.553  1.0
  O  O23  1  0.724  0.000  0.447  1.0
  O  O24  1  0.447  0.000  0.724  1.0
  O  O25  1  0.276  0.722  0.276  1.0
[/CIF]
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The compound described by Eu2Al3O8 crystallizes in the cubic I-43m space group. Eu(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form EuO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with three equivalent Eu(1)O6 octahedra. Al(1) is bonded to four equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Eu(1)O6 octahedra and corners with four equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 64°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Eu(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Eu(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Eu2Al3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.786
_cell_length_b   7.786
_cell_length_c   7.786
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   363.341
_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
  Eu  Eu0  1  0.297  0.297  0.297  1.0
  Eu  Eu1  1  0.703  0.000  0.000  1.0
  Eu  Eu2  1  0.000  0.703  0.000  1.0
  Eu  Eu3  1  0.000  0.000  0.703  1.0
  Al  Al4  1  0.250  0.750  0.500  1.0
  Al  Al5  1  0.750  0.250  0.500  1.0
  Al  Al6  1  0.750  0.500  0.250  1.0
  Al  Al7  1  0.250  0.500  0.750  1.0
  Al  Al8  1  0.500  0.250  0.750  1.0
  Al  Al9  1  0.500  0.750  0.250  1.0
  O  O10  1  0.790  0.790  0.790  1.0
  O  O11  1  0.210  0.000  0.000  1.0
  O  O12  1  0.000  0.210  0.000  1.0
  O  O13  1  0.000  0.000  0.210  1.0
  O  O14  1  0.278  0.553  0.553  1.0
  O  O15  1  0.722  0.276  0.276  1.0
  O  O16  1  0.000  0.447  0.724  1.0
  O  O17  1  0.553  0.553  0.278  1.0
  O  O18  1  0.000  0.724  0.447  1.0
  O  O19  1  0.276  0.276  0.722  1.0
  O  O20  1  0.447  0.724  0.000  1.0
  O  O21  1  0.724  0.447  0.000  1.0
  O  O22  1  0.553  0.278  0.553  1.0
  O  O23  1  0.724  0.000  0.447  1.0
  O  O24  1  0.447  0.000  0.724  1.0
  O  O25  1  0.276  0.722  0.276  1.0
[/CIF]
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