The structure described by NaK(BH4)2 crystallizes in the trigonal R-3 space group. K(1) is bonded to six equivalent H(1) and six equivalent H(2) atoms to form KH12 cuboctahedra that share corners with six equivalent Na(1)H6 octahedra, edges with six equivalent K(1)H12 cuboctahedra, and edges with six equivalent B(1)H4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. Na(1) is bonded to six equivalent H(2) atoms to form NaH6 octahedra that share corners with six equivalent K(1)H12 cuboctahedra and corners with six equivalent B(1)H4 tetrahedra. B(1) is bonded to one H(1) and three equivalent H(2) atoms to form BH4 tetrahedra that share corners with three equivalent Na(1)H6 octahedra and edges with three equivalent K(1)H12 cuboctahedra. The corner-sharing octahedral tilt angles are 66°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to three equivalent K(1) and one B(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one K(1), one Na(1), and one B(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNa(BH4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.857
_cell_length_b   7.857
_cell_length_c   7.857
_cell_angle_alpha   33.520
_cell_angle_beta   33.520
_cell_angle_gamma   33.520
_symmetry_Int_Tables_number   1
_cell_volume   131.726
_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  0.500  0.500  0.500  1.0
  Na  Na1  1  0.000  0.000  0.000  1.0
  B  B2  1  0.256  0.256  0.256  1.0
  B  B3  1  0.744  0.744  0.744  1.0
  H  H4  1  0.800  0.800  0.800  1.0
  H  H5  1  0.015  0.528  0.635  1.0
  H  H6  1  0.985  0.472  0.365  1.0
  H  H7  1  0.472  0.365  0.985  1.0
  H  H8  1  0.528  0.635  0.015  1.0
  H  H9  1  0.200  0.200  0.200  1.0
  H  H10  1  0.635  0.015  0.528  1.0
  H  H11  1  0.365  0.985  0.472  1.0
[/CIF]
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The structure described by NaK(BH4)2 crystallizes in the trigonal R-3 space group. K(1) is bonded to six equivalent H(1) and six equivalent H(2) atoms to form KH12 cuboctahedra that share corners with six equivalent Na(1)H6 octahedra, edges with six equivalent K(1)H12 cuboctahedra, and edges with six equivalent B(1)H4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. Na(1) is bonded to six equivalent H(2) atoms to form NaH6 octahedra that share corners with six equivalent K(1)H12 cuboctahedra and corners with six equivalent B(1)H4 tetrahedra. B(1) is bonded to one H(1) and three equivalent H(2) atoms to form BH4 tetrahedra that share corners with three equivalent Na(1)H6 octahedra and edges with three equivalent K(1)H12 cuboctahedra. The corner-sharing octahedral tilt angles are 66°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to three equivalent K(1) and one B(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one K(1), one Na(1), and one B(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNa(BH4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.857
_cell_length_b   7.857
_cell_length_c   7.857
_cell_angle_alpha   33.520
_cell_angle_beta   33.520
_cell_angle_gamma   33.520
_symmetry_Int_Tables_number   1
_cell_volume   131.726
_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  0.500  0.500  0.500  1.0
  Na  Na1  1  0.000  0.000  0.000  1.0
  B  B2  1  0.256  0.256  0.256  1.0
  B  B3  1  0.744  0.744  0.744  1.0
  H  H4  1  0.800  0.800  0.800  1.0
  H  H5  1  0.015  0.528  0.635  1.0
  H  H6  1  0.985  0.472  0.365  1.0
  H  H7  1  0.472  0.365  0.985  1.0
  H  H8  1  0.528  0.635  0.015  1.0
  H  H9  1  0.200  0.200  0.200  1.0
  H  H10  1  0.635  0.015  0.528  1.0
  H  H11  1  0.365  0.985  0.472  1.0
[/CIF]
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