The material described by NaAlH2 crystallizes in the tetragonal I4_1/amd space group. Na(1) is bonded to six equivalent H(1) atoms to form distorted edge-sharing NaH6 octahedra. Al(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent H(1) atoms. H(1) is bonded to three equivalent Na(1) and two equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing HNa3Al2 trigonal bipyramids. is represented by the CIF card [CIF]
data_NaAlH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.944
_cell_length_b   6.944
_cell_length_c   6.944
_cell_angle_alpha   128.388
_cell_angle_beta   128.388
_cell_angle_gamma   75.997
_symmetry_Int_Tables_number   1
_cell_volume   199.982
_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  0.875  0.625  0.250  1.0
  Na  Na1  1  0.375  0.625  0.750  1.0
  Na  Na2  1  0.375  0.625  0.250  1.0
  Na  Na3  1  0.375  0.125  0.750  1.0
  Al  Al4  1  0.375  0.125  0.250  1.0
  Al  Al5  1  0.875  0.125  0.750  1.0
  Al  Al6  1  0.875  0.125  0.250  1.0
  Al  Al7  1  0.875  0.625  0.750  1.0
  H  H8  1  0.174  0.361  0.186  1.0
  H  H9  1  0.174  0.988  0.814  1.0
  H  H10  1  0.111  0.424  0.686  1.0
  H  H11  1  0.576  0.889  0.314  1.0
  H  H12  1  0.738  0.424  0.314  1.0
  H  H13  1  0.576  0.262  0.686  1.0
  H  H14  1  0.639  0.826  0.814  1.0
  H  H15  1  0.012  0.826  0.186  1.0
[/CIF]
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The material described by NaAlH2 crystallizes in the tetragonal I4_1/amd space group. Na(1) is bonded to six equivalent H(1) atoms to form distorted edge-sharing NaH6 octahedra. Al(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent H(1) atoms. H(1) is bonded to three equivalent Na(1) and two equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing HNa3Al2 trigonal bipyramids. is represented by the CIF card [CIF]
data_NaAlH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.944
_cell_length_b   6.944
_cell_length_c   6.944
_cell_angle_alpha   128.388
_cell_angle_beta   128.388
_cell_angle_gamma   75.997
_symmetry_Int_Tables_number   1
_cell_volume   199.982
_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  0.875  0.625  0.250  1.0
  Na  Na1  1  0.375  0.625  0.750  1.0
  Na  Na2  1  0.375  0.625  0.250  1.0
  Na  Na3  1  0.375  0.125  0.750  1.0
  Al  Al4  1  0.375  0.125  0.250  1.0
  Al  Al5  1  0.875  0.125  0.750  1.0
  Al  Al6  1  0.875  0.125  0.250  1.0
  Al  Al7  1  0.875  0.625  0.750  1.0
  H  H8  1  0.174  0.361  0.186  1.0
  H  H9  1  0.174  0.988  0.814  1.0
  H  H10  1  0.111  0.424  0.686  1.0
  H  H11  1  0.576  0.889  0.314  1.0
  H  H12  1  0.738  0.424  0.314  1.0
  H  H13  1  0.576  0.262  0.686  1.0
  H  H14  1  0.639  0.826  0.814  1.0
  H  H15  1  0.012  0.826  0.186  1.0
[/CIF]
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