The compound described by Mg7NbH16 is Fluorite-derived structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a body-centered cubic geometry to four equivalent H(1) and four equivalent H(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight 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 HMg3Nb tetrahedra that share corners with six equivalent H(2)Mg4 tetrahedra, corners with ten equivalent H(1)Mg3Nb tetrahedra, edges with three equivalent H(1)Mg3Nb tetrahedra, and edges with three equivalent H(2)Mg4 tetrahedra. In the second H site, H(2) is bonded to one Mg(2) and three equivalent Mg(1) atoms to form HMg4 tetrahedra that share corners with six equivalent H(1)Mg3Nb tetrahedra, corners with ten equivalent H(2)Mg4 tetrahedra, edges with three equivalent H(1)Mg3Nb tetrahedra, and edges with three equivalent H(2)Mg4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg7NbH16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.629
_cell_length_b   6.629
_cell_length_c   6.629
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   205.987
_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
  Mg  Mg6  1  0.500  0.500  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.000  1.0
  H  H8  1  0.880  0.880  0.360  1.0
  H  H9  1  0.880  0.360  0.880  1.0
  H  H10  1  0.360  0.880  0.880  1.0
  H  H11  1  0.880  0.880  0.880  1.0
  H  H12  1  0.120  0.120  0.640  1.0
  H  H13  1  0.120  0.640  0.120  1.0
  H  H14  1  0.640  0.120  0.120  1.0
  H  H15  1  0.120  0.120  0.120  1.0
  H  H16  1  0.628  0.628  0.117  1.0
  H  H17  1  0.628  0.117  0.628  1.0
  H  H18  1  0.117  0.628  0.628  1.0
  H  H19  1  0.628  0.628  0.628  1.0
  H  H20  1  0.372  0.372  0.883  1.0
  H  H21  1  0.372  0.883  0.372  1.0
  H  H22  1  0.883  0.372  0.372  1.0
  H  H23  1  0.372  0.372  0.372  1.0
[/CIF]
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The compound described by Mg7NbH16 is Fluorite-derived structured and crystallizes in the cubic Fm-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a body-centered cubic geometry to four equivalent H(1) and four equivalent H(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight 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 HMg3Nb tetrahedra that share corners with six equivalent H(2)Mg4 tetrahedra, corners with ten equivalent H(1)Mg3Nb tetrahedra, edges with three equivalent H(1)Mg3Nb tetrahedra, and edges with three equivalent H(2)Mg4 tetrahedra. In the second H site, H(2) is bonded to one Mg(2) and three equivalent Mg(1) atoms to form HMg4 tetrahedra that share corners with six equivalent H(1)Mg3Nb tetrahedra, corners with ten equivalent H(2)Mg4 tetrahedra, edges with three equivalent H(1)Mg3Nb tetrahedra, and edges with three equivalent H(2)Mg4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg7NbH16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.629
_cell_length_b   6.629
_cell_length_c   6.629
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   205.987
_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
  Mg  Mg6  1  0.500  0.500  0.500  1.0
  Nb  Nb7  1  0.000  0.000  0.000  1.0
  H  H8  1  0.880  0.880  0.360  1.0
  H  H9  1  0.880  0.360  0.880  1.0
  H  H10  1  0.360  0.880  0.880  1.0
  H  H11  1  0.880  0.880  0.880  1.0
  H  H12  1  0.120  0.120  0.640  1.0
  H  H13  1  0.120  0.640  0.120  1.0
  H  H14  1  0.640  0.120  0.120  1.0
  H  H15  1  0.120  0.120  0.120  1.0
  H  H16  1  0.628  0.628  0.117  1.0
  H  H17  1  0.628  0.117  0.628  1.0
  H  H18  1  0.117  0.628  0.628  1.0
  H  H19  1  0.628  0.628  0.628  1.0
  H  H20  1  0.372  0.372  0.883  1.0
  H  H21  1  0.372  0.883  0.372  1.0
  H  H22  1  0.883  0.372  0.372  1.0
  H  H23  1  0.372  0.372  0.372  1.0
[/CIF]
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