The crystal structure described by La4H9 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a distorted body-centered cubic geometry to one H(2) and eight equivalent H(1) atoms. In the second La site, La(2) is bonded in a distorted body-centered cubic geometry to two equivalent H(2) and eight equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form HLa4 tetrahedra that share corners with three equivalent H(2)La6 octahedra, corners with sixteen equivalent H(1)La4 tetrahedra, edges with six equivalent H(1)La4 tetrahedra, and  a faceface with one H(2)La6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. In the second H site, H(2) is bonded to two equivalent La(1) and four equivalent La(2) atoms to form HLa6 octahedra that share corners with four equivalent H(2)La6 octahedra, corners with twenty-four equivalent H(1)La4 tetrahedra, and faces with eight equivalent H(1)La4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_La4H9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.617
_cell_length_b   5.617
_cell_length_c   6.927
_cell_angle_alpha   113.920
_cell_angle_beta   113.920
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   179.034
_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
  La  La0  1  0.754  0.754  0.508  1.0
  La  La1  1  0.246  0.246  0.492  1.0
  La  La2  1  0.000  0.500  0.000  1.0
  La  La3  1  0.500  0.000  0.000  1.0
  H  H4  1  0.132  0.132  0.746  1.0
  H  H5  1  0.615  0.615  0.746  1.0
  H  H6  1  0.615  0.132  0.746  1.0
  H  H7  1  0.132  0.615  0.746  1.0
  H  H8  1  0.868  0.868  0.254  1.0
  H  H9  1  0.385  0.385  0.254  1.0
  H  H10  1  0.385  0.868  0.254  1.0
  H  H11  1  0.868  0.385  0.254  1.0
  H  H12  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by La4H9 crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a distorted body-centered cubic geometry to one H(2) and eight equivalent H(1) atoms. In the second La site, La(2) is bonded in a distorted body-centered cubic geometry to two equivalent H(2) and eight equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded to two equivalent La(1) and two equivalent La(2) atoms to form HLa4 tetrahedra that share corners with three equivalent H(2)La6 octahedra, corners with sixteen equivalent H(1)La4 tetrahedra, edges with six equivalent H(1)La4 tetrahedra, and  a faceface with one H(2)La6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. In the second H site, H(2) is bonded to two equivalent La(1) and four equivalent La(2) atoms to form HLa6 octahedra that share corners with four equivalent H(2)La6 octahedra, corners with twenty-four equivalent H(1)La4 tetrahedra, and faces with eight equivalent H(1)La4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_La4H9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.617
_cell_length_b   5.617
_cell_length_c   6.927
_cell_angle_alpha   113.920
_cell_angle_beta   113.920
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   179.034
_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
  La  La0  1  0.754  0.754  0.508  1.0
  La  La1  1  0.246  0.246  0.492  1.0
  La  La2  1  0.000  0.500  0.000  1.0
  La  La3  1  0.500  0.000  0.000  1.0
  H  H4  1  0.132  0.132  0.746  1.0
  H  H5  1  0.615  0.615  0.746  1.0
  H  H6  1  0.615  0.132  0.746  1.0
  H  H7  1  0.132  0.615  0.746  1.0
  H  H8  1  0.868  0.868  0.254  1.0
  H  H9  1  0.385  0.385  0.254  1.0
  H  H10  1  0.385  0.868  0.254  1.0
  H  H11  1  0.868  0.385  0.254  1.0
  H  H12  1  0.000  0.000  0.000  1.0
[/CIF]
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