The structure described by Sr2FeAl3O8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(8), and two equivalent O(4) atoms. Fe(1) is bonded to one O(1), one O(2), one O(4), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form AlO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. In the second Al site, Al(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Sr(1), one Al(1), and one Al(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Sr(2), one Fe(1), and one Al(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(2), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Al(2), and one Al(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(2) atom. is represented by the CIF card [CIF]
data_Sr2Al3FeO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.001
_cell_length_b   5.303
_cell_length_c   8.564
_cell_angle_alpha   86.067
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   407.839
_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
  Sr  Sr0  1  0.997  0.251  0.514  1.0
  Sr  Sr1  1  0.497  0.749  0.486  1.0
  Sr  Sr2  1  0.986  0.201  0.970  1.0
  Sr  Sr3  1  0.486  0.799  0.030  1.0
  Al  Al4  1  0.838  0.726  0.205  1.0
  Al  Al5  1  0.338  0.274  0.795  1.0
  Al  Al6  1  0.671  0.220  0.291  1.0
  Al  Al7  1  0.171  0.780  0.709  1.0
  Al  Al8  1  0.163  0.801  0.324  1.0
  Al  Al9  1  0.663  0.199  0.676  1.0
  Fe  Fe10  1  0.826  0.711  0.807  1.0
  Fe  Fe11  1  0.326  0.289  0.193  1.0
  O  O12  1  0.314  0.614  0.268  1.0
  O  O13  1  0.814  0.386  0.732  1.0
  O  O14  1  0.650  0.906  0.790  1.0
  O  O15  1  0.150  0.094  0.210  1.0
  O  O16  1  0.487  0.346  0.664  1.0
  O  O17  1  0.987  0.654  0.336  1.0
  O  O18  1  0.891  0.639  0.016  1.0
  O  O19  1  0.391  0.361  0.984  1.0
  O  O20  1  0.295  0.945  0.827  1.0
  O  O21  1  0.795  0.055  0.173  1.0
  O  O22  1  0.173  0.444  0.735  1.0
  O  O23  1  0.673  0.556  0.265  1.0
  O  O24  1  0.217  0.881  0.514  1.0
  O  O25  1  0.717  0.119  0.486  1.0
  O  O26  1  0.991  0.907  0.734  1.0
  O  O27  1  0.491  0.093  0.266  1.0
[/CIF]
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The structure described by Sr2FeAl3O8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(6), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(5), one O(6), one O(8), and two equivalent O(4) atoms. Fe(1) is bonded to one O(1), one O(2), one O(4), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra, and corners with two equivalent Al(3)O4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form AlO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, and corners with two equivalent Al(2)O4 tetrahedra. In the second Al site, Al(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form AlO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, and corners with two equivalent Al(1)O4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(2), one O(3), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Al(2)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(3) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Sr(1), one Al(1), and one Al(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Sr(2), one Fe(1), and one Al(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2), one Al(1), and one Al(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(2), one Al(1), and one Al(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Al(2), and one Al(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Fe(1), and one Al(2) atom. is represented by the CIF card [CIF]
data_Sr2Al3FeO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.001
_cell_length_b   5.303
_cell_length_c   8.564
_cell_angle_alpha   86.067
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   407.839
_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
  Sr  Sr0  1  0.997  0.251  0.514  1.0
  Sr  Sr1  1  0.497  0.749  0.486  1.0
  Sr  Sr2  1  0.986  0.201  0.970  1.0
  Sr  Sr3  1  0.486  0.799  0.030  1.0
  Al  Al4  1  0.838  0.726  0.205  1.0
  Al  Al5  1  0.338  0.274  0.795  1.0
  Al  Al6  1  0.671  0.220  0.291  1.0
  Al  Al7  1  0.171  0.780  0.709  1.0
  Al  Al8  1  0.163  0.801  0.324  1.0
  Al  Al9  1  0.663  0.199  0.676  1.0
  Fe  Fe10  1  0.826  0.711  0.807  1.0
  Fe  Fe11  1  0.326  0.289  0.193  1.0
  O  O12  1  0.314  0.614  0.268  1.0
  O  O13  1  0.814  0.386  0.732  1.0
  O  O14  1  0.650  0.906  0.790  1.0
  O  O15  1  0.150  0.094  0.210  1.0
  O  O16  1  0.487  0.346  0.664  1.0
  O  O17  1  0.987  0.654  0.336  1.0
  O  O18  1  0.891  0.639  0.016  1.0
  O  O19  1  0.391  0.361  0.984  1.0
  O  O20  1  0.295  0.945  0.827  1.0
  O  O21  1  0.795  0.055  0.173  1.0
  O  O22  1  0.173  0.444  0.735  1.0
  O  O23  1  0.673  0.556  0.265  1.0
  O  O24  1  0.217  0.881  0.514  1.0
  O  O25  1  0.717  0.119  0.486  1.0
  O  O26  1  0.991  0.907  0.734  1.0
  O  O27  1  0.491  0.093  0.266  1.0
[/CIF]
.