The material structure described by NdNi4MgH4 crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded in a 3-coordinate geometry to one H(2) and two equivalent H(1) atoms. Nd(1) is bonded in a 7-coordinate geometry to one H(3), two equivalent H(2), and four equivalent H(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 3-coordinate geometry to one H(2) and two equivalent H(1) atoms. In the second Ni site, Ni(2) is bonded in a water-like geometry to one H(2) and one H(3) atom. In the third Ni site, Ni(3) is bonded in a water-like geometry to one H(1) and one H(3) atom. There are three inequivalent H sites. In the first H site, H(1) is bonded to one Mg(1), two equivalent Nd(1), one Ni(1), and one Ni(3) atom to form distorted HNd2MgNi2 trigonal bipyramids that share corners with three equivalent H(3)NdNi3 tetrahedra, corners with two equivalent H(2)Nd2MgNi2 trigonal bipyramids, corners with four equivalent H(1)Nd2MgNi2 trigonal bipyramids, edges with two equivalent H(1)Nd2MgNi2 trigonal bipyramids, and edges with two equivalent H(2)Nd2MgNi2 trigonal bipyramids. In the second H site, H(2) is bonded to one Mg(1), two equivalent Nd(1), one Ni(1), and one Ni(2) atom to form distorted HNd2MgNi2 trigonal bipyramids that share corners with three equivalent H(3)NdNi3 tetrahedra, corners with two equivalent H(2)Nd2MgNi2 trigonal bipyramids, corners with four equivalent H(1)Nd2MgNi2 trigonal bipyramids, and edges with four equivalent H(1)Nd2MgNi2 trigonal bipyramids. In the third H site, H(3) is bonded to one Nd(1), one Ni(2), and two equivalent Ni(3) atoms to form corner-sharing HNdNi3 tetrahedra. is represented by the CIF card [CIF]
data_NdMg(NiH)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.052
_cell_length_b   5.470
_cell_length_c   7.329
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   202.522
_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
  Nd  Nd0  1  0.500  0.702  0.502  1.0
  Nd  Nd1  1  0.000  0.298  0.002  1.0
  Mg  Mg2  1  0.500  0.182  0.723  1.0
  Mg  Mg3  1  0.000  0.818  0.223  1.0
  Ni  Ni4  1  0.500  0.551  0.122  1.0
  Ni  Ni5  1  0.000  0.449  0.622  1.0
  Ni  Ni6  1  0.500  0.007  0.104  1.0
  Ni  Ni7  1  0.000  0.993  0.604  1.0
  Ni  Ni8  1  0.256  0.771  0.879  1.0
  Ni  Ni9  1  0.744  0.771  0.879  1.0
  Ni  Ni10  1  0.244  0.229  0.379  1.0
  Ni  Ni11  1  0.756  0.229  0.379  1.0
  H  H12  1  0.248  0.490  0.258  1.0
  H  H13  1  0.752  0.490  0.258  1.0
  H  H14  1  0.252  0.510  0.758  1.0
  H  H15  1  0.748  0.510  0.758  1.0
  H  H16  1  0.500  0.279  0.011  1.0
  H  H17  1  0.000  0.721  0.511  1.0
  H  H18  1  0.500  0.062  0.324  1.0
  H  H19  1  0.000  0.938  0.824  1.0
[/CIF]
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The material structure described by NdNi4MgH4 crystallizes in the orthorhombic Pmn2_1 space group. Mg(1) is bonded in a 3-coordinate geometry to one H(2) and two equivalent H(1) atoms. Nd(1) is bonded in a 7-coordinate geometry to one H(3), two equivalent H(2), and four equivalent H(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 3-coordinate geometry to one H(2) and two equivalent H(1) atoms. In the second Ni site, Ni(2) is bonded in a water-like geometry to one H(2) and one H(3) atom. In the third Ni site, Ni(3) is bonded in a water-like geometry to one H(1) and one H(3) atom. There are three inequivalent H sites. In the first H site, H(1) is bonded to one Mg(1), two equivalent Nd(1), one Ni(1), and one Ni(3) atom to form distorted HNd2MgNi2 trigonal bipyramids that share corners with three equivalent H(3)NdNi3 tetrahedra, corners with two equivalent H(2)Nd2MgNi2 trigonal bipyramids, corners with four equivalent H(1)Nd2MgNi2 trigonal bipyramids, edges with two equivalent H(1)Nd2MgNi2 trigonal bipyramids, and edges with two equivalent H(2)Nd2MgNi2 trigonal bipyramids. In the second H site, H(2) is bonded to one Mg(1), two equivalent Nd(1), one Ni(1), and one Ni(2) atom to form distorted HNd2MgNi2 trigonal bipyramids that share corners with three equivalent H(3)NdNi3 tetrahedra, corners with two equivalent H(2)Nd2MgNi2 trigonal bipyramids, corners with four equivalent H(1)Nd2MgNi2 trigonal bipyramids, and edges with four equivalent H(1)Nd2MgNi2 trigonal bipyramids. In the third H site, H(3) is bonded to one Nd(1), one Ni(2), and two equivalent Ni(3) atoms to form corner-sharing HNdNi3 tetrahedra. is represented by the CIF card [CIF]
data_NdMg(NiH)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.052
_cell_length_b   5.470
_cell_length_c   7.329
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   202.522
_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
  Nd  Nd0  1  0.500  0.702  0.502  1.0
  Nd  Nd1  1  0.000  0.298  0.002  1.0
  Mg  Mg2  1  0.500  0.182  0.723  1.0
  Mg  Mg3  1  0.000  0.818  0.223  1.0
  Ni  Ni4  1  0.500  0.551  0.122  1.0
  Ni  Ni5  1  0.000  0.449  0.622  1.0
  Ni  Ni6  1  0.500  0.007  0.104  1.0
  Ni  Ni7  1  0.000  0.993  0.604  1.0
  Ni  Ni8  1  0.256  0.771  0.879  1.0
  Ni  Ni9  1  0.744  0.771  0.879  1.0
  Ni  Ni10  1  0.244  0.229  0.379  1.0
  Ni  Ni11  1  0.756  0.229  0.379  1.0
  H  H12  1  0.248  0.490  0.258  1.0
  H  H13  1  0.752  0.490  0.258  1.0
  H  H14  1  0.252  0.510  0.758  1.0
  H  H15  1  0.748  0.510  0.758  1.0
  H  H16  1  0.500  0.279  0.011  1.0
  H  H17  1  0.000  0.721  0.511  1.0
  H  H18  1  0.500  0.062  0.324  1.0
  H  H19  1  0.000  0.938  0.824  1.0
[/CIF]
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