The material described by NaAlH2 crystallizes in the tetragonal I4_1/a space group. Na(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent H(1) atoms. Al(1) is bonded in a square co-planar geometry to four equivalent H(1) atoms. H(1) is bonded to two equivalent Na(1) and two equivalent Al(1) atoms to form a mixture of distorted edge and corner-sharing HNa2Al2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaAlH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.540
_cell_length_b   6.540
_cell_length_c   6.786
_cell_angle_alpha   118.807
_cell_angle_beta   118.807
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.433
_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
  Na  Na0  1  0.625  0.875  0.250  1.0
  Na  Na1  1  0.625  0.375  0.250  1.0
  Na  Na2  1  0.625  0.375  0.750  1.0
  Na  Na3  1  0.125  0.375  0.750  1.0
  Al  Al4  1  0.125  0.375  0.250  1.0
  Al  Al5  1  0.125  0.875  0.250  1.0
  Al  Al6  1  0.125  0.875  0.750  1.0
  Al  Al7  1  0.625  0.875  0.750  1.0
  H  H8  1  0.202  0.807  0.004  1.0
  H  H9  1  0.802  0.197  0.004  1.0
  H  H10  1  0.447  0.952  0.504  1.0
  H  H11  1  0.048  0.943  0.496  1.0
  H  H12  1  0.057  0.552  0.504  1.0
  H  H13  1  0.448  0.553  0.496  1.0
  H  H14  1  0.803  0.798  0.996  1.0
  H  H15  1  0.193  0.198  0.996  1.0
[/CIF]
.
The material described by NaAlH2 crystallizes in the tetragonal I4_1/a space group. Na(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent H(1) atoms. Al(1) is bonded in a square co-planar geometry to four equivalent H(1) atoms. H(1) is bonded to two equivalent Na(1) and two equivalent Al(1) atoms to form a mixture of distorted edge and corner-sharing HNa2Al2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaAlH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.540
_cell_length_b   6.540
_cell_length_c   6.786
_cell_angle_alpha   118.807
_cell_angle_beta   118.807
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   212.433
_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
  Na  Na0  1  0.625  0.875  0.250  1.0
  Na  Na1  1  0.625  0.375  0.250  1.0
  Na  Na2  1  0.625  0.375  0.750  1.0
  Na  Na3  1  0.125  0.375  0.750  1.0
  Al  Al4  1  0.125  0.375  0.250  1.0
  Al  Al5  1  0.125  0.875  0.250  1.0
  Al  Al6  1  0.125  0.875  0.750  1.0
  Al  Al7  1  0.625  0.875  0.750  1.0
  H  H8  1  0.202  0.807  0.004  1.0
  H  H9  1  0.802  0.197  0.004  1.0
  H  H10  1  0.447  0.952  0.504  1.0
  H  H11  1  0.048  0.943  0.496  1.0
  H  H12  1  0.057  0.552  0.504  1.0
  H  H13  1  0.448  0.553  0.496  1.0
  H  H14  1  0.803  0.798  0.996  1.0
  H  H15  1  0.193  0.198  0.996  1.0
[/CIF]
.