The structure described by K3AlH6 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to four equivalent H(1) and four equivalent H(2) atoms to form distorted KH8 hexagonal bipyramids that share corners with four equivalent K(1)H8 hexagonal bipyramids, edges with six equivalent K(1)H8 hexagonal bipyramids, and edges with four equivalent Al(1)H6 octahedra. In the second K site, K(2) is bonded in a linear geometry to two equivalent H(2) atoms. Al(1) is bonded to two equivalent H(2) and four equivalent H(1) atoms to form AlH6 octahedra that share edges with eight equivalent K(1)H8 hexagonal bipyramids. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted trigonal planar geometry to two equivalent K(1) and one Al(1) atom. In the second H site, H(2) is bonded to one K(2), four equivalent K(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing HK5Al octahedra. The corner-sharing octahedral tilt angles range from 0-15°. is represented by the CIF file [CIF]
data_K3AlH6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.203
_cell_length_b   6.203
_cell_length_c   6.203
_cell_angle_alpha   123.708
_cell_angle_beta   123.708
_cell_angle_gamma   83.689
_symmetry_Int_Tables_number   1
_cell_volume   158.292
_cell_formula_units_Z   1
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
  K  K0  1  0.250  0.750  0.500  1.0
  K  K1  1  0.750  0.250  0.500  1.0
  K  K2  1  0.500  0.500  0.000  1.0
  Al  Al3  1  0.000  0.000  0.000  1.0
  H  H4  1  0.000  0.704  0.704  1.0
  H  H5  1  0.704  0.000  0.704  1.0
  H  H6  1  0.296  0.000  0.296  1.0
  H  H7  1  0.000  0.296  0.296  1.0
  H  H8  1  0.209  0.209  0.000  1.0
  H  H9  1  0.791  0.791  0.000  1.0
[/CIF]
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The structure described by K3AlH6 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to four equivalent H(1) and four equivalent H(2) atoms to form distorted KH8 hexagonal bipyramids that share corners with four equivalent K(1)H8 hexagonal bipyramids, edges with six equivalent K(1)H8 hexagonal bipyramids, and edges with four equivalent Al(1)H6 octahedra. In the second K site, K(2) is bonded in a linear geometry to two equivalent H(2) atoms. Al(1) is bonded to two equivalent H(2) and four equivalent H(1) atoms to form AlH6 octahedra that share edges with eight equivalent K(1)H8 hexagonal bipyramids. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted trigonal planar geometry to two equivalent K(1) and one Al(1) atom. In the second H site, H(2) is bonded to one K(2), four equivalent K(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing HK5Al octahedra. The corner-sharing octahedral tilt angles range from 0-15°. is represented by the CIF file [CIF]
data_K3AlH6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.203
_cell_length_b   6.203
_cell_length_c   6.203
_cell_angle_alpha   123.708
_cell_angle_beta   123.708
_cell_angle_gamma   83.689
_symmetry_Int_Tables_number   1
_cell_volume   158.292
_cell_formula_units_Z   1
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
  K  K0  1  0.250  0.750  0.500  1.0
  K  K1  1  0.750  0.250  0.500  1.0
  K  K2  1  0.500  0.500  0.000  1.0
  Al  Al3  1  0.000  0.000  0.000  1.0
  H  H4  1  0.000  0.704  0.704  1.0
  H  H5  1  0.704  0.000  0.704  1.0
  H  H6  1  0.296  0.000  0.296  1.0
  H  H7  1  0.000  0.296  0.296  1.0
  H  H8  1  0.209  0.209  0.000  1.0
  H  H9  1  0.791  0.791  0.000  1.0
[/CIF]
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