The material described by La2Ni9AlH crystallizes in the monoclinic Pm space group. La(1) is bonded in a distorted single-bond geometry to two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), three equivalent Ni(1), three equivalent Ni(3), and one H(1) atom. There are seven inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent La(1), one Ni(2), one Ni(4), one Ni(5), one Ni(6), one Ni(7), three equivalent Ni(3), and one Al(1) atom. In the second Ni site, Ni(2) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(3), two equivalent Ni(5), and two equivalent Ni(6) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(2)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(2)La4Ni8 cuboctahedra, faces with four equivalent Ni(5)La4Ni8 cuboctahedra, and faces with four equivalent Ni(6)La4Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded in a 12-coordinate geometry to three equivalent La(1), one Ni(2), one Ni(4), one Ni(5), one Ni(6), one Ni(7), three equivalent Ni(1), and one Al(1) atom. In the fourth Ni site, Ni(4) is bonded in a 2-coordinate geometry to two equivalent Ni(1), two equivalent Ni(3), and two equivalent Al(1) atoms. In the fifth Ni site, Ni(5) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(6) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(5)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(5)La4Ni8 cuboctahedra, faces with four equivalent Ni(2)La4Ni8 cuboctahedra, and faces with four equivalent Ni(6)La4Ni8 cuboctahedra. In the sixth Ni site, Ni(6) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(5) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(6)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(6)La4Ni8 cuboctahedra, faces with four equivalent Ni(2)La4Ni8 cuboctahedra, and faces with four equivalent Ni(5)La4Ni8 cuboctahedra. In the seventh Ni site, Ni(7) is bonded in a distorted single-bond geometry to two equivalent Ni(1), two equivalent Ni(3), and one H(1) atom. Al(1) is bonded in a distorted single-bond geometry to two equivalent Ni(1), two equivalent Ni(3), two equivalent Ni(4), and one H(1) atom. H(1) is bonded to two equivalent La(1), one Ni(7), and one Al(1) atom to form distorted HLa2AlNi trigonal pyramids that share corners with four equivalent Ni(2)La4Ni8 cuboctahedra, corners with four equivalent Ni(5)La4Ni8 cuboctahedra, and corners with four equivalent Ni(6)La4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_La2AlNi9H
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.090
_cell_length_b   4.977
_cell_length_c   5.010
_cell_angle_alpha   60.606
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   175.736
_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  0.266  0.995  0.004  1.0
  La  La1  1  0.734  0.995  0.004  1.0
  Al  Al2  1  0.000  0.492  0.507  1.0
  Ni  Ni3  1  0.252  0.331  0.333  1.0
  Ni  Ni4  1  0.748  0.331  0.333  1.0
  Ni  Ni5  1  0.500  0.497  0.504  1.0
  Ni  Ni6  1  0.253  0.660  0.683  1.0
  Ni  Ni7  1  0.000  0.497  0.002  1.0
  Ni  Ni8  1  0.500  0.996  0.503  1.0
  Ni  Ni9  1  0.500  0.495  0.006  1.0
  Ni  Ni10  1  0.747  0.660  0.683  1.0
  Ni  Ni11  1  0.000  0.997  0.495  1.0
  H  H12  1  0.000  0.920  0.216  1.0
[/CIF]
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The material described by La2Ni9AlH crystallizes in the monoclinic Pm space group. La(1) is bonded in a distorted single-bond geometry to two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), three equivalent Ni(1), three equivalent Ni(3), and one H(1) atom. There are seven inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent La(1), one Ni(2), one Ni(4), one Ni(5), one Ni(6), one Ni(7), three equivalent Ni(3), and one Al(1) atom. In the second Ni site, Ni(2) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(3), two equivalent Ni(5), and two equivalent Ni(6) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(2)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(2)La4Ni8 cuboctahedra, faces with four equivalent Ni(5)La4Ni8 cuboctahedra, and faces with four equivalent Ni(6)La4Ni8 cuboctahedra. In the third Ni site, Ni(3) is bonded in a 12-coordinate geometry to three equivalent La(1), one Ni(2), one Ni(4), one Ni(5), one Ni(6), one Ni(7), three equivalent Ni(1), and one Al(1) atom. In the fourth Ni site, Ni(4) is bonded in a 2-coordinate geometry to two equivalent Ni(1), two equivalent Ni(3), and two equivalent Al(1) atoms. In the fifth Ni site, Ni(5) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(6) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(5)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(5)La4Ni8 cuboctahedra, faces with four equivalent Ni(2)La4Ni8 cuboctahedra, and faces with four equivalent Ni(6)La4Ni8 cuboctahedra. In the sixth Ni site, Ni(6) is bonded to four equivalent La(1), two equivalent Ni(1), two equivalent Ni(2), two equivalent Ni(3), and two equivalent Ni(5) atoms to form NiLa4Ni8 cuboctahedra that share corners with four equivalent Ni(6)La4Ni8 cuboctahedra, corners with four equivalent H(1)La2AlNi trigonal pyramids, edges with two equivalent Ni(6)La4Ni8 cuboctahedra, faces with four equivalent Ni(2)La4Ni8 cuboctahedra, and faces with four equivalent Ni(5)La4Ni8 cuboctahedra. In the seventh Ni site, Ni(7) is bonded in a distorted single-bond geometry to two equivalent Ni(1), two equivalent Ni(3), and one H(1) atom. Al(1) is bonded in a distorted single-bond geometry to two equivalent Ni(1), two equivalent Ni(3), two equivalent Ni(4), and one H(1) atom. H(1) is bonded to two equivalent La(1), one Ni(7), and one Al(1) atom to form distorted HLa2AlNi trigonal pyramids that share corners with four equivalent Ni(2)La4Ni8 cuboctahedra, corners with four equivalent Ni(5)La4Ni8 cuboctahedra, and corners with four equivalent Ni(6)La4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_La2AlNi9H
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.090
_cell_length_b   4.977
_cell_length_c   5.010
_cell_angle_alpha   60.606
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   175.736
_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  0.266  0.995  0.004  1.0
  La  La1  1  0.734  0.995  0.004  1.0
  Al  Al2  1  0.000  0.492  0.507  1.0
  Ni  Ni3  1  0.252  0.331  0.333  1.0
  Ni  Ni4  1  0.748  0.331  0.333  1.0
  Ni  Ni5  1  0.500  0.497  0.504  1.0
  Ni  Ni6  1  0.253  0.660  0.683  1.0
  Ni  Ni7  1  0.000  0.497  0.002  1.0
  Ni  Ni8  1  0.500  0.996  0.503  1.0
  Ni  Ni9  1  0.500  0.495  0.006  1.0
  Ni  Ni10  1  0.747  0.660  0.683  1.0
  Ni  Ni11  1  0.000  0.997  0.495  1.0
  H  H12  1  0.000  0.920  0.216  1.0
[/CIF]
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