The crystal structure described by SrAl2O4 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 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(3), one O(5), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), one O(6), and one O(8) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the fourth Al site, Al(4) is bonded to one O(1), one O(3), one O(5), and one O(8) atom to form corner-sharing AlO4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Sr(1), one Al(3), and one Al(4) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), one Al(1), and one Al(4) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Sr(2), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(2), 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 Al(1), and one Al(4) atom. is represented by the CIF file [CIF]
data_SrAl2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.816
_cell_length_b   5.162
_cell_length_c   8.453
_cell_angle_alpha   86.584
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   384.007
_cell_formula_units_Z   4
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  0.492  0.201  0.970  1.0
  Sr  Sr1  1  0.992  0.799  0.030  1.0
  Sr  Sr2  1  0.499  0.251  0.509  1.0
  Sr  Sr3  1  0.999  0.749  0.491  1.0
  Al  Al4  1  0.669  0.798  0.319  1.0
  Al  Al5  1  0.169  0.202  0.681  1.0
  Al  Al6  1  0.167  0.222  0.293  1.0
  Al  Al7  1  0.667  0.778  0.707  1.0
  Al  Al8  1  0.337  0.729  0.200  1.0
  Al  Al9  1  0.837  0.271  0.800  1.0
  Al  Al10  1  0.330  0.714  0.810  1.0
  Al  Al11  1  0.830  0.286  0.190  1.0
  O  O12  1  0.385  0.647  0.008  1.0
  O  O13  1  0.885  0.353  0.992  1.0
  O  O14  1  0.716  0.882  0.512  1.0
  O  O15  1  0.216  0.118  0.488  1.0
  O  O16  1  0.166  0.906  0.795  1.0
  O  O17  1  0.666  0.094  0.205  1.0
  O  O18  1  0.795  0.937  0.826  1.0
  O  O19  1  0.295  0.063  0.174  1.0
  O  O20  1  0.484  0.899  0.733  1.0
  O  O21  1  0.984  0.101  0.267  1.0
  O  O22  1  0.990  0.346  0.673  1.0
  O  O23  1  0.490  0.654  0.327  1.0
  O  O24  1  0.170  0.563  0.265  1.0
  O  O25  1  0.670  0.437  0.735  1.0
  O  O26  1  0.315  0.411  0.730  1.0
  O  O27  1  0.815  0.589  0.270  1.0
[/CIF]
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The crystal structure described by SrAl2O4 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 6-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(3), one O(5), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), one O(6), and one O(8) atom to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the third Al site, Al(3) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form corner-sharing AlO4 tetrahedra. In the fourth Al site, Al(4) is bonded to one O(1), one O(3), one O(5), and one O(8) atom to form corner-sharing AlO4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Sr(1), one Al(3), and one Al(4) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(2), one Al(1), and one Al(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), one Al(1), and one Al(4) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and one Al(3) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Al(2), and one Al(4) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Sr(2), one Al(1), and one Al(3) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Sr(2), 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 Al(1), and one Al(4) atom. is represented by the CIF file [CIF]
data_SrAl2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.816
_cell_length_b   5.162
_cell_length_c   8.453
_cell_angle_alpha   86.584
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   384.007
_cell_formula_units_Z   4
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  0.492  0.201  0.970  1.0
  Sr  Sr1  1  0.992  0.799  0.030  1.0
  Sr  Sr2  1  0.499  0.251  0.509  1.0
  Sr  Sr3  1  0.999  0.749  0.491  1.0
  Al  Al4  1  0.669  0.798  0.319  1.0
  Al  Al5  1  0.169  0.202  0.681  1.0
  Al  Al6  1  0.167  0.222  0.293  1.0
  Al  Al7  1  0.667  0.778  0.707  1.0
  Al  Al8  1  0.337  0.729  0.200  1.0
  Al  Al9  1  0.837  0.271  0.800  1.0
  Al  Al10  1  0.330  0.714  0.810  1.0
  Al  Al11  1  0.830  0.286  0.190  1.0
  O  O12  1  0.385  0.647  0.008  1.0
  O  O13  1  0.885  0.353  0.992  1.0
  O  O14  1  0.716  0.882  0.512  1.0
  O  O15  1  0.216  0.118  0.488  1.0
  O  O16  1  0.166  0.906  0.795  1.0
  O  O17  1  0.666  0.094  0.205  1.0
  O  O18  1  0.795  0.937  0.826  1.0
  O  O19  1  0.295  0.063  0.174  1.0
  O  O20  1  0.484  0.899  0.733  1.0
  O  O21  1  0.984  0.101  0.267  1.0
  O  O22  1  0.990  0.346  0.673  1.0
  O  O23  1  0.490  0.654  0.327  1.0
  O  O24  1  0.170  0.563  0.265  1.0
  O  O25  1  0.670  0.437  0.735  1.0
  O  O26  1  0.315  0.411  0.730  1.0
  O  O27  1  0.815  0.589  0.270  1.0
[/CIF]
.