The structure described by Mg6LaNb crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Nb(1) atoms to form MgLa2Mg8Nb2 cuboctahedra that share corners with four equivalent La(1)Mg10Nb2 cuboctahedra, corners with four equivalent Nb(1)La2Mg10 cuboctahedra, corners with ten equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent La(1)Mg10Nb2 cuboctahedra, edges with two equivalent Nb(1)La2Mg10 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent La(1), and two equivalent Nb(1) atoms. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent La(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(1), and two equivalent Nb(1) atoms. La(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms to form LaMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)La2Mg10 cuboctahedra, corners with six equivalent La(1)Mg10Nb2 cuboctahedra, corners with eight equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent Nb(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. Nb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent La(1) atoms to form NbLa2Mg10 cuboctahedra that share corners with four equivalent La(1)Mg10Nb2 cuboctahedra, corners with six equivalent Nb(1)La2Mg10 cuboctahedra, corners with eight equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent La(1)Mg10Nb2 cuboctahedra, edges with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. is represented by the CIF file [CIF]
data_LaMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.183
_cell_length_b   6.142
_cell_length_c   6.693
_cell_angle_alpha   117.309
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.309
_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  0.500  0.173  0.347  1.0
  Mg  Mg1  1  0.500  0.671  0.842  1.0
  Mg  Mg2  1  0.500  0.170  0.842  1.0
  Mg  Mg3  1  1.000  0.817  0.164  1.0
  Mg  Mg4  1  0.000  0.347  0.164  1.0
  Mg  Mg5  1  0.000  0.341  0.683  1.0
  Mg  Mg6  1  0.000  0.815  0.631  1.0
  Nb  Nb7  1  0.500  0.664  0.329  1.0
[/CIF]
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The structure described by Mg6LaNb crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent La(1), and two equivalent Nb(1) atoms to form MgLa2Mg8Nb2 cuboctahedra that share corners with four equivalent La(1)Mg10Nb2 cuboctahedra, corners with four equivalent Nb(1)La2Mg10 cuboctahedra, corners with ten equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent La(1)Mg10Nb2 cuboctahedra, edges with two equivalent Nb(1)La2Mg10 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent La(1), and two equivalent Nb(1) atoms. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent La(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(1), and two equivalent Nb(1) atoms. La(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Nb(1) atoms to form LaMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)La2Mg10 cuboctahedra, corners with six equivalent La(1)Mg10Nb2 cuboctahedra, corners with eight equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent Nb(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. Nb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent La(1) atoms to form NbLa2Mg10 cuboctahedra that share corners with four equivalent La(1)Mg10Nb2 cuboctahedra, corners with six equivalent Nb(1)La2Mg10 cuboctahedra, corners with eight equivalent Mg(1)La2Mg8Nb2 cuboctahedra, edges with two equivalent La(1)Mg10Nb2 cuboctahedra, edges with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra, faces with two equivalent La(1)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(1)La2Mg8Nb2 cuboctahedra. is represented by the CIF file [CIF]
data_LaMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.183
_cell_length_b   6.142
_cell_length_c   6.693
_cell_angle_alpha   117.309
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.309
_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  0.500  0.173  0.347  1.0
  Mg  Mg1  1  0.500  0.671  0.842  1.0
  Mg  Mg2  1  0.500  0.170  0.842  1.0
  Mg  Mg3  1  1.000  0.817  0.164  1.0
  Mg  Mg4  1  0.000  0.347  0.164  1.0
  Mg  Mg5  1  0.000  0.341  0.683  1.0
  Mg  Mg6  1  0.000  0.815  0.631  1.0
  Nb  Nb7  1  0.500  0.664  0.329  1.0
[/CIF]
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