The compound described by Na3AlH6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms to form NaH6 octahedra that share corners with six equivalent Al(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 30-37°. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to two equivalent H(1), two equivalent H(3), and three equivalent H(2) atoms. Al(1) is bonded to two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms to form AlH6 octahedra that share corners with six equivalent Na(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 30-37°. There are three inequivalent H sites. In the first H site, H(1) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one Al(1) atom. In the second H site, H(2) is bonded in a 3-coordinate geometry to one Na(1), three equivalent Na(2), and one Al(1) atom. In the third H site, H(3) is bonded to one Na(1), two equivalent Na(2), and one Al(1) atom to form distorted corner-sharing HNa3Al tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3AlH6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.293
_cell_length_b   5.490
_cell_length_c   7.620
_cell_angle_alpha   90.000
_cell_angle_beta   89.983
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.445
_cell_formula_units_Z   2
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  0.000  0.000  0.500  1.0
  Na  Na1  1  0.500  0.500  0.000  1.0
  Na  Na2  1  0.489  0.047  0.754  1.0
  Na  Na3  1  0.011  0.547  0.746  1.0
  Na  Na4  1  0.511  0.953  0.246  1.0
  Na  Na5  1  0.989  0.453  0.254  1.0
  Al  Al6  1  0.000  0.000  0.000  1.0
  Al  Al7  1  0.500  0.500  0.500  1.0
  H  H8  1  0.661  0.233  0.437  1.0
  H  H9  1  0.839  0.733  0.063  1.0
  H  H10  1  0.339  0.767  0.563  1.0
  H  H11  1  0.161  0.267  0.937  1.0
  H  H12  1  0.728  0.170  0.043  1.0
  H  H13  1  0.772  0.670  0.457  1.0
  H  H14  1  0.272  0.830  0.957  1.0
  H  H15  1  0.228  0.330  0.543  1.0
  H  H16  1  0.100  0.048  0.217  1.0
  H  H17  1  0.400  0.548  0.283  1.0
  H  H18  1  0.900  0.952  0.783  1.0
  H  H19  1  0.600  0.452  0.717  1.0
[/CIF]
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The compound described by Na3AlH6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms to form NaH6 octahedra that share corners with six equivalent Al(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 30-37°. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to two equivalent H(1), two equivalent H(3), and three equivalent H(2) atoms. Al(1) is bonded to two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms to form AlH6 octahedra that share corners with six equivalent Na(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 30-37°. There are three inequivalent H sites. In the first H site, H(1) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one Al(1) atom. In the second H site, H(2) is bonded in a 3-coordinate geometry to one Na(1), three equivalent Na(2), and one Al(1) atom. In the third H site, H(3) is bonded to one Na(1), two equivalent Na(2), and one Al(1) atom to form distorted corner-sharing HNa3Al tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3AlH6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.293
_cell_length_b   5.490
_cell_length_c   7.620
_cell_angle_alpha   90.000
_cell_angle_beta   89.983
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   221.445
_cell_formula_units_Z   2
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  0.000  0.000  0.500  1.0
  Na  Na1  1  0.500  0.500  0.000  1.0
  Na  Na2  1  0.489  0.047  0.754  1.0
  Na  Na3  1  0.011  0.547  0.746  1.0
  Na  Na4  1  0.511  0.953  0.246  1.0
  Na  Na5  1  0.989  0.453  0.254  1.0
  Al  Al6  1  0.000  0.000  0.000  1.0
  Al  Al7  1  0.500  0.500  0.500  1.0
  H  H8  1  0.661  0.233  0.437  1.0
  H  H9  1  0.839  0.733  0.063  1.0
  H  H10  1  0.339  0.767  0.563  1.0
  H  H11  1  0.161  0.267  0.937  1.0
  H  H12  1  0.728  0.170  0.043  1.0
  H  H13  1  0.772  0.670  0.457  1.0
  H  H14  1  0.272  0.830  0.957  1.0
  H  H15  1  0.228  0.330  0.543  1.0
  H  H16  1  0.100  0.048  0.217  1.0
  H  H17  1  0.400  0.548  0.283  1.0
  H  H18  1  0.900  0.952  0.783  1.0
  H  H19  1  0.600  0.452  0.717  1.0
[/CIF]
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