The structure described by LiAlH4 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one H(1), one H(3), one H(4), and two equivalent H(2) atoms to form LiH5 trigonal bipyramids that share corners with five equivalent Al(1)H4 tetrahedra and  an edgeedge with one Li(1)H5 trigonal bipyramid. Al(1) is bonded to one H(1), one H(2), one H(3), and one H(4) atom to form AlH4 tetrahedra that share corners with five equivalent Li(1)H5 trigonal bipyramids. There are four inequivalent H sites. In the first H site, H(1) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. In the second H site, H(2) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Al(1) atom. In the third H site, H(3) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. is represented by the CIF file [CIF]
data_LiAlH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.825
_cell_length_b   4.862
_cell_length_c   7.870
_cell_angle_alpha   68.195
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   277.979
_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
  Li  Li0  1  0.965  0.429  0.324  1.0
  Li  Li1  1  0.465  0.571  0.176  1.0
  Li  Li2  1  0.035  0.571  0.676  1.0
  Li  Li3  1  0.535  0.429  0.824  1.0
  Al  Al4  1  0.702  0.860  0.432  1.0
  Al  Al5  1  0.202  0.140  0.068  1.0
  Al  Al6  1  0.298  0.140  0.568  1.0
  Al  Al7  1  0.798  0.860  0.932  1.0
  H  H8  1  0.599  0.818  0.264  1.0
  H  H9  1  0.099  0.182  0.236  1.0
  H  H10  1  0.401  0.182  0.736  1.0
  H  H11  1  0.901  0.818  0.764  1.0
  H  H12  1  0.872  0.646  0.478  1.0
  H  H13  1  0.372  0.354  0.022  1.0
  H  H14  1  0.128  0.354  0.522  1.0
  H  H15  1  0.628  0.646  0.978  1.0
  H  H16  1  0.583  0.762  0.614  1.0
  H  H17  1  0.083  0.238  0.886  1.0
  H  H18  1  0.417  0.238  0.386  1.0
  H  H19  1  0.917  0.762  0.114  1.0
  H  H20  1  0.764  0.202  0.372  1.0
  H  H21  1  0.264  0.798  0.128  1.0
  H  H22  1  0.236  0.798  0.628  1.0
  H  H23  1  0.736  0.202  0.872  1.0
[/CIF]
.
The structure described by LiAlH4 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one H(1), one H(3), one H(4), and two equivalent H(2) atoms to form LiH5 trigonal bipyramids that share corners with five equivalent Al(1)H4 tetrahedra and  an edgeedge with one Li(1)H5 trigonal bipyramid. Al(1) is bonded to one H(1), one H(2), one H(3), and one H(4) atom to form AlH4 tetrahedra that share corners with five equivalent Li(1)H5 trigonal bipyramids. There are four inequivalent H sites. In the first H site, H(1) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. In the second H site, H(2) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Al(1) atom. In the third H site, H(3) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a bent 150 degrees geometry to one Li(1) and one Al(1) atom. is represented by the CIF file [CIF]
data_LiAlH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.825
_cell_length_b   4.862
_cell_length_c   7.870
_cell_angle_alpha   68.195
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   277.979
_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
  Li  Li0  1  0.965  0.429  0.324  1.0
  Li  Li1  1  0.465  0.571  0.176  1.0
  Li  Li2  1  0.035  0.571  0.676  1.0
  Li  Li3  1  0.535  0.429  0.824  1.0
  Al  Al4  1  0.702  0.860  0.432  1.0
  Al  Al5  1  0.202  0.140  0.068  1.0
  Al  Al6  1  0.298  0.140  0.568  1.0
  Al  Al7  1  0.798  0.860  0.932  1.0
  H  H8  1  0.599  0.818  0.264  1.0
  H  H9  1  0.099  0.182  0.236  1.0
  H  H10  1  0.401  0.182  0.736  1.0
  H  H11  1  0.901  0.818  0.764  1.0
  H  H12  1  0.872  0.646  0.478  1.0
  H  H13  1  0.372  0.354  0.022  1.0
  H  H14  1  0.128  0.354  0.522  1.0
  H  H15  1  0.628  0.646  0.978  1.0
  H  H16  1  0.583  0.762  0.614  1.0
  H  H17  1  0.083  0.238  0.886  1.0
  H  H18  1  0.417  0.238  0.386  1.0
  H  H19  1  0.917  0.762  0.114  1.0
  H  H20  1  0.764  0.202  0.372  1.0
  H  H21  1  0.264  0.798  0.128  1.0
  H  H22  1  0.236  0.798  0.628  1.0
  H  H23  1  0.736  0.202  0.872  1.0
[/CIF]
.