The material described by Sr2AlH7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 11-coordinate geometry to one H(3), one H(4), one H(5), one H(7), two equivalent H(1), two equivalent H(2), and three equivalent H(6) atoms. In the second Sr site, Sr(2) is bonded in a 10-coordinate geometry to one H(1), one H(2), one H(4), two equivalent H(3), two equivalent H(5), and three equivalent H(7) atoms. Al(1) is bonded in an octahedral geometry to one H(1), one H(2), one H(3), one H(4), one H(5), and one H(6) atom. There are seven inequivalent H sites. In the first H site, H(3) is bonded in a 1-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Al(1) atom. In the second H site, H(4) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(2), and one Al(1) atom. In the third H site, H(5) is bonded in a 1-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Al(1) atom. In the fourth H site, H(6) is bonded in a distorted single-bond geometry to three equivalent Sr(1) and one Al(1) atom. In the fifth H site, H(7) is bonded to one Sr(1) and three equivalent Sr(2) atoms to form a mixture of edge and corner-sharing HSr4 tetrahedra. In the sixth H site, H(1) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one Al(1) atom. In the seventh H site, H(2) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one Al(1) atom. is represented by the CIF card [CIF]
data_Sr2AlH7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.349
_cell_length_b   8.349
_cell_length_c   7.988
_cell_angle_alpha   69.817
_cell_angle_beta   69.817
_cell_angle_gamma   71.468
_symmetry_Int_Tables_number   1
_cell_volume   477.943
_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  0.264  0.924  0.478  1.0
  Sr  Sr1  1  0.076  0.736  0.022  1.0
  Sr  Sr2  1  0.736  0.076  0.522  1.0
  Sr  Sr3  1  0.924  0.264  0.978  1.0
  Sr  Sr4  1  0.290  0.432  0.477  1.0
  Sr  Sr5  1  0.568  0.710  0.023  1.0
  Sr  Sr6  1  0.710  0.568  0.523  1.0
  Sr  Sr7  1  0.432  0.290  0.977  1.0
  Al  Al8  1  0.321  0.024  0.808  1.0
  Al  Al9  1  0.976  0.679  0.692  1.0
  Al  Al10  1  0.679  0.976  0.192  1.0
  Al  Al11  1  0.024  0.321  0.308  1.0
  H  H12  1  0.394  0.108  0.574  1.0
  H  H13  1  0.892  0.606  0.926  1.0
  H  H14  1  0.606  0.892  0.426  1.0
  H  H15  1  0.108  0.394  0.074  1.0
  H  H16  1  0.387  0.808  0.774  1.0
  H  H17  1  0.192  0.613  0.726  1.0
  H  H18  1  0.613  0.192  0.226  1.0
  H  H19  1  0.808  0.387  0.274  1.0
  H  H20  1  0.524  0.008  0.832  1.0
  H  H21  1  0.992  0.476  0.668  1.0
  H  H22  1  0.476  0.992  0.168  1.0
  H  H23  1  0.008  0.524  0.332  1.0
  H  H24  1  0.260  0.918  0.041  1.0
  H  H25  1  0.082  0.740  0.459  1.0
  H  H26  1  0.740  0.082  0.959  1.0
  H  H27  1  0.918  0.260  0.541  1.0
  H  H28  1  0.244  0.233  0.833  1.0
  H  H29  1  0.767  0.756  0.667  1.0
  H  H30  1  0.756  0.767  0.167  1.0
  H  H31  1  0.233  0.244  0.333  1.0
  H  H32  1  0.117  0.032  0.793  1.0
  H  H33  1  0.968  0.883  0.707  1.0
  H  H34  1  0.883  0.968  0.207  1.0
  H  H35  1  0.032  0.117  0.293  1.0
  H  H36  1  0.341  0.542  0.127  1.0
  H  H37  1  0.458  0.659  0.373  1.0
  H  H38  1  0.659  0.458  0.873  1.0
  H  H39  1  0.542  0.341  0.627  1.0
[/CIF]
.
The material described by Sr2AlH7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 11-coordinate geometry to one H(3), one H(4), one H(5), one H(7), two equivalent H(1), two equivalent H(2), and three equivalent H(6) atoms. In the second Sr site, Sr(2) is bonded in a 10-coordinate geometry to one H(1), one H(2), one H(4), two equivalent H(3), two equivalent H(5), and three equivalent H(7) atoms. Al(1) is bonded in an octahedral geometry to one H(1), one H(2), one H(3), one H(4), one H(5), and one H(6) atom. There are seven inequivalent H sites. In the first H site, H(3) is bonded in a 1-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Al(1) atom. In the second H site, H(4) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(2), and one Al(1) atom. In the third H site, H(5) is bonded in a 1-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Al(1) atom. In the fourth H site, H(6) is bonded in a distorted single-bond geometry to three equivalent Sr(1) and one Al(1) atom. In the fifth H site, H(7) is bonded to one Sr(1) and three equivalent Sr(2) atoms to form a mixture of edge and corner-sharing HSr4 tetrahedra. In the sixth H site, H(1) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one Al(1) atom. In the seventh H site, H(2) is bonded in a distorted single-bond geometry to one Sr(2), two equivalent Sr(1), and one Al(1) atom. is represented by the CIF card [CIF]
data_Sr2AlH7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.349
_cell_length_b   8.349
_cell_length_c   7.988
_cell_angle_alpha   69.817
_cell_angle_beta   69.817
_cell_angle_gamma   71.468
_symmetry_Int_Tables_number   1
_cell_volume   477.943
_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  0.264  0.924  0.478  1.0
  Sr  Sr1  1  0.076  0.736  0.022  1.0
  Sr  Sr2  1  0.736  0.076  0.522  1.0
  Sr  Sr3  1  0.924  0.264  0.978  1.0
  Sr  Sr4  1  0.290  0.432  0.477  1.0
  Sr  Sr5  1  0.568  0.710  0.023  1.0
  Sr  Sr6  1  0.710  0.568  0.523  1.0
  Sr  Sr7  1  0.432  0.290  0.977  1.0
  Al  Al8  1  0.321  0.024  0.808  1.0
  Al  Al9  1  0.976  0.679  0.692  1.0
  Al  Al10  1  0.679  0.976  0.192  1.0
  Al  Al11  1  0.024  0.321  0.308  1.0
  H  H12  1  0.394  0.108  0.574  1.0
  H  H13  1  0.892  0.606  0.926  1.0
  H  H14  1  0.606  0.892  0.426  1.0
  H  H15  1  0.108  0.394  0.074  1.0
  H  H16  1  0.387  0.808  0.774  1.0
  H  H17  1  0.192  0.613  0.726  1.0
  H  H18  1  0.613  0.192  0.226  1.0
  H  H19  1  0.808  0.387  0.274  1.0
  H  H20  1  0.524  0.008  0.832  1.0
  H  H21  1  0.992  0.476  0.668  1.0
  H  H22  1  0.476  0.992  0.168  1.0
  H  H23  1  0.008  0.524  0.332  1.0
  H  H24  1  0.260  0.918  0.041  1.0
  H  H25  1  0.082  0.740  0.459  1.0
  H  H26  1  0.740  0.082  0.959  1.0
  H  H27  1  0.918  0.260  0.541  1.0
  H  H28  1  0.244  0.233  0.833  1.0
  H  H29  1  0.767  0.756  0.667  1.0
  H  H30  1  0.756  0.767  0.167  1.0
  H  H31  1  0.233  0.244  0.333  1.0
  H  H32  1  0.117  0.032  0.793  1.0
  H  H33  1  0.968  0.883  0.707  1.0
  H  H34  1  0.883  0.968  0.207  1.0
  H  H35  1  0.032  0.117  0.293  1.0
  H  H36  1  0.341  0.542  0.127  1.0
  H  H37  1  0.458  0.659  0.373  1.0
  H  H38  1  0.659  0.458  0.873  1.0
  H  H39  1  0.542  0.341  0.627  1.0
[/CIF]
.