The structure described by NaMg6Nb is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded to two equivalent Mg(2); four Mg(1,1,1); four Mg(3,3); and two equivalent Nb(1) atoms to form NaMg10Nb2 cuboctahedra that share corners with four equivalent Mg(2)Na2Mg10 cuboctahedra; corners with six equivalent Na(1)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(2)Na2Mg10 cuboctahedra; edges with four equivalent Nb(1)Na2Mg10 cuboctahedra; edges with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Nb2 cuboctahedra. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the second Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the third Mg site, Mg(2) is bonded to two equivalent Na(1); two equivalent Mg(4); four Mg(1,1,1); and four Mg(3,3) atoms to form MgNa2Mg10 cuboctahedra that share corners with four equivalent Na(1)Mg10Nb2 cuboctahedra; corners with six equivalent Mg(2)Na2Mg10 cuboctahedra; edges with two equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Nb(1)Na2Mg10 cuboctahedra. In the fourth Mg site, Mg(3) is bonded to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with ten Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; and faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra. In the fifth Mg site, Mg(3) is bonded to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with ten Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; and faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra. In the sixth Mg site, Mg(4) is bonded to two equivalent Mg(2); four Mg(1,1); four Mg(3,3); and two equivalent Nb(1) atoms to form MgMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with six equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; edges with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Na(1)Mg10Nb2 cuboctahedra. In the seventh Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. Nb(1) is bonded to two equivalent Na(1); two equivalent Mg(4); four Mg(1,1); and four Mg(3,3) atoms to form NbNa2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with six equivalent Nb(1)Na2Mg10 cuboctahedra; corners with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Mg(2)Na2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.326
_cell_length_b   6.326
_cell_length_c   5.107
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.234
_symmetry_Int_Tables_number   1
_cell_volume   178.385
_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
  Na  Na0  1  0.835  0.165  0.000  1.0
  Mg  Mg1  1  0.824  0.644  0.000  1.0
  Mg  Mg2  1  0.356  0.176  0.000  1.0
  Mg  Mg3  1  0.334  0.666  0.000  1.0
  Mg  Mg4  1  0.667  0.832  0.500  1.0
  Mg  Mg5  1  0.168  0.333  0.500  1.0
  Mg  Mg6  1  0.163  0.837  0.500  1.0
  Nb  Nb7  1  0.654  0.346  0.500  1.0
[/CIF]
.
The structure described by NaMg6Nb is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Amm2 space group. Na(1) is bonded to two equivalent Mg(2); four Mg(1,1,1); four Mg(3,3); and two equivalent Nb(1) atoms to form NaMg10Nb2 cuboctahedra that share corners with four equivalent Mg(2)Na2Mg10 cuboctahedra; corners with six equivalent Na(1)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(2)Na2Mg10 cuboctahedra; edges with four equivalent Nb(1)Na2Mg10 cuboctahedra; edges with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Mg(4)Mg10Nb2 cuboctahedra. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the second Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the third Mg site, Mg(2) is bonded to two equivalent Na(1); two equivalent Mg(4); four Mg(1,1,1); and four Mg(3,3) atoms to form MgNa2Mg10 cuboctahedra that share corners with four equivalent Na(1)Mg10Nb2 cuboctahedra; corners with six equivalent Mg(2)Na2Mg10 cuboctahedra; edges with two equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Nb(1)Na2Mg10 cuboctahedra. In the fourth Mg site, Mg(3) is bonded to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with ten Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; and faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra. In the fifth Mg site, Mg(3) is bonded to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms to form distorted MgNa2Mg8Nb2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with ten Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with two equivalent Mg(3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; and faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra. In the sixth Mg site, Mg(4) is bonded to two equivalent Mg(2); four Mg(1,1); four Mg(3,3); and two equivalent Nb(1) atoms to form MgMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)Na2Mg10 cuboctahedra; corners with six equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Nb(1)Na2Mg10 cuboctahedra; edges with four equivalent Mg(2)Na2Mg10 cuboctahedra; edges with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(2)Na2Mg10 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Na(1)Mg10Nb2 cuboctahedra. In the seventh Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Na(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. Nb(1) is bonded to two equivalent Na(1); two equivalent Mg(4); four Mg(1,1); and four Mg(3,3) atoms to form NbNa2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra; corners with six equivalent Nb(1)Na2Mg10 cuboctahedra; corners with eight Mg(3,3)Na2Mg8Nb2 cuboctahedra; edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra; edges with four equivalent Na(1)Mg10Nb2 cuboctahedra; edges with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; faces with two equivalent Na(1)Mg10Nb2 cuboctahedra; faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra; faces with two equivalent Nb(1)Na2Mg10 cuboctahedra; faces with four Mg(3,3)Na2Mg8Nb2 cuboctahedra; and faces with six equivalent Mg(2)Na2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.326
_cell_length_b   6.326
_cell_length_c   5.107
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.234
_symmetry_Int_Tables_number   1
_cell_volume   178.385
_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
  Na  Na0  1  0.835  0.165  0.000  1.0
  Mg  Mg1  1  0.824  0.644  0.000  1.0
  Mg  Mg2  1  0.356  0.176  0.000  1.0
  Mg  Mg3  1  0.334  0.666  0.000  1.0
  Mg  Mg4  1  0.667  0.832  0.500  1.0
  Mg  Mg5  1  0.168  0.333  0.500  1.0
  Mg  Mg6  1  0.163  0.837  0.500  1.0
  Nb  Nb7  1  0.654  0.346  0.500  1.0
[/CIF]
.