The crystal structure described by Mg6NbH16 crystallizes in the cubic Fm-3m space group. Mg(1) is bonded in a body-centered cubic geometry to four equivalent H(1) and four equivalent H(2) atoms. Nb(1) is bonded in a body-centered cubic geometry to eight equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded to three equivalent Mg(1) and one Nb(1) atom to form a mixture of corner and edge-sharing HMg3Nb tetrahedra. In the second H site, H(2) is bonded in a trigonal planar geometry to three equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_Mg6NbH16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.731
_cell_length_b   6.731
_cell_length_c   6.731
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   215.667
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.500  0.000  0.500  1.0
  Mg  Mg2  1  0.000  0.500  0.500  1.0
  Mg  Mg3  1  0.500  0.500  0.000  1.0
  Mg  Mg4  1  0.000  0.500  0.000  1.0
  Mg  Mg5  1  0.500  0.000  0.000  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  H  H7  1  0.884  0.884  0.347  1.0
  H  H8  1  0.884  0.347  0.884  1.0
  H  H9  1  0.347  0.884  0.884  1.0
  H  H10  1  0.884  0.884  0.884  1.0
  H  H11  1  0.116  0.116  0.653  1.0
  H  H12  1  0.116  0.653  0.116  1.0
  H  H13  1  0.653  0.116  0.116  1.0
  H  H14  1  0.116  0.116  0.116  1.0
  H  H15  1  0.643  0.643  0.071  1.0
  H  H16  1  0.643  0.071  0.643  1.0
  H  H17  1  0.071  0.643  0.643  1.0
  H  H18  1  0.643  0.643  0.643  1.0
  H  H19  1  0.357  0.357  0.929  1.0
  H  H20  1  0.357  0.929  0.357  1.0
  H  H21  1  0.929  0.357  0.357  1.0
  H  H22  1  0.357  0.357  0.357  1.0
[/CIF]
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The crystal structure described by Mg6NbH16 crystallizes in the cubic Fm-3m space group. Mg(1) is bonded in a body-centered cubic geometry to four equivalent H(1) and four equivalent H(2) atoms. Nb(1) is bonded in a body-centered cubic geometry to eight equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded to three equivalent Mg(1) and one Nb(1) atom to form a mixture of corner and edge-sharing HMg3Nb tetrahedra. In the second H site, H(2) is bonded in a trigonal planar geometry to three equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_Mg6NbH16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.731
_cell_length_b   6.731
_cell_length_c   6.731
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   215.667
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.500  0.000  0.500  1.0
  Mg  Mg2  1  0.000  0.500  0.500  1.0
  Mg  Mg3  1  0.500  0.500  0.000  1.0
  Mg  Mg4  1  0.000  0.500  0.000  1.0
  Mg  Mg5  1  0.500  0.000  0.000  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  H  H7  1  0.884  0.884  0.347  1.0
  H  H8  1  0.884  0.347  0.884  1.0
  H  H9  1  0.347  0.884  0.884  1.0
  H  H10  1  0.884  0.884  0.884  1.0
  H  H11  1  0.116  0.116  0.653  1.0
  H  H12  1  0.116  0.653  0.116  1.0
  H  H13  1  0.653  0.116  0.116  1.0
  H  H14  1  0.116  0.116  0.116  1.0
  H  H15  1  0.643  0.643  0.071  1.0
  H  H16  1  0.643  0.071  0.643  1.0
  H  H17  1  0.071  0.643  0.643  1.0
  H  H18  1  0.643  0.643  0.643  1.0
  H  H19  1  0.357  0.357  0.929  1.0
  H  H20  1  0.357  0.929  0.357  1.0
  H  H21  1  0.929  0.357  0.357  1.0
  H  H22  1  0.357  0.357  0.357  1.0
[/CIF]
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