The material structure described by BeAlH5 crystallizes in the monoclinic P2_1 space group. Be(1) is bonded to one H(2), one H(3), and two equivalent H(1) atoms to form BeH4 tetrahedra that share corners with two equivalent Al(1)H6 octahedra and corners with two equivalent Be(1)H4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-55°. Al(1) is bonded to one H(2), one H(3), two equivalent H(4), and two equivalent H(5) atoms to form AlH6 octahedra that share corners with four equivalent Al(1)H6 octahedra and corners with two equivalent Be(1)H4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-43°. There are five inequivalent H sites. In the first H site, H(1) is bonded in a bent 150 degrees geometry to two equivalent Be(1) atoms. In the second H site, H(2) is bonded in a bent 120 degrees geometry to one Be(1) and one Al(1) atom. In the third H site, H(3) is bonded in a bent 120 degrees geometry to one Be(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. In the fifth H site, H(5) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_BeAlH5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.306
_cell_length_b   4.770
_cell_length_c   6.254
_cell_angle_alpha   89.407
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   128.456
_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
  Be  Be0  1  0.230  0.002  0.623  1.0
  Be  Be1  1  0.730  0.998  0.377  1.0
  Al  Al2  1  0.990  0.243  1.000  1.0
  Al  Al3  1  0.490  0.757  0.000  1.0
  H  H4  1  0.466  0.110  0.485  1.0
  H  H5  1  0.966  0.890  0.515  1.0
  H  H6  1  0.321  0.760  0.748  1.0
  H  H7  1  0.821  0.240  0.252  1.0
  H  H8  1  0.162  0.247  0.749  1.0
  H  H9  1  0.662  0.753  0.251  1.0
  H  H10  1  0.740  0.001  0.902  1.0
  H  H11  1  0.240  0.999  0.098  1.0
  H  H12  1  0.740  0.501  0.913  1.0
  H  H13  1  0.240  0.499  0.087  1.0
[/CIF]
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The material structure described by BeAlH5 crystallizes in the monoclinic P2_1 space group. Be(1) is bonded to one H(2), one H(3), and two equivalent H(1) atoms to form BeH4 tetrahedra that share corners with two equivalent Al(1)H6 octahedra and corners with two equivalent Be(1)H4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-55°. Al(1) is bonded to one H(2), one H(3), two equivalent H(4), and two equivalent H(5) atoms to form AlH6 octahedra that share corners with four equivalent Al(1)H6 octahedra and corners with two equivalent Be(1)H4 tetrahedra. The corner-sharing octahedral tilt angles range from 37-43°. There are five inequivalent H sites. In the first H site, H(1) is bonded in a bent 150 degrees geometry to two equivalent Be(1) atoms. In the second H site, H(2) is bonded in a bent 120 degrees geometry to one Be(1) and one Al(1) atom. In the third H site, H(3) is bonded in a bent 120 degrees geometry to one Be(1) and one Al(1) atom. In the fourth H site, H(4) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. In the fifth H site, H(5) is bonded in a bent 150 degrees geometry to two equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_BeAlH5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.306
_cell_length_b   4.770
_cell_length_c   6.254
_cell_angle_alpha   89.407
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   128.456
_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
  Be  Be0  1  0.230  0.002  0.623  1.0
  Be  Be1  1  0.730  0.998  0.377  1.0
  Al  Al2  1  0.990  0.243  1.000  1.0
  Al  Al3  1  0.490  0.757  0.000  1.0
  H  H4  1  0.466  0.110  0.485  1.0
  H  H5  1  0.966  0.890  0.515  1.0
  H  H6  1  0.321  0.760  0.748  1.0
  H  H7  1  0.821  0.240  0.252  1.0
  H  H8  1  0.162  0.247  0.749  1.0
  H  H9  1  0.662  0.753  0.251  1.0
  H  H10  1  0.740  0.001  0.902  1.0
  H  H11  1  0.240  0.999  0.098  1.0
  H  H12  1  0.740  0.501  0.913  1.0
  H  H13  1  0.240  0.499  0.087  1.0
[/CIF]
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