The material structure described by Na2MgNb2O6 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent O(2), two equivalent O(4), and four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. Mg(1) is bonded in a rectangular see-saw-like geometry to one Na(1), two equivalent O(3), and two equivalent O(4) atoms. Nb(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Na(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Nb(1) atoms to form distorted ONa4Nb2 octahedra that share edges with two equivalent O(2)Na4Nb2 octahedra and faces with four equivalent O(4)Na2MgNb2 trigonal bipyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Mg(1), and two equivalent Nb(1) atoms to form distorted ONa2MgNb2 trigonal bipyramids that share corners with three equivalent O(4)Na2MgNb2 trigonal bipyramids,  an edgeedge with one O(4)Na2MgNb2 trigonal bipyramid, and faces with two equivalent O(2)Na4Nb2 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2MgNb2O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.122
_cell_length_b   5.835
_cell_length_c   5.835
_cell_angle_alpha   90.339
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   140.359
_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  0.500  0.404  0.904  1.0
  Na  Na1  1  0.500  0.071  0.571  1.0
  Mg  Mg2  1  0.500  0.739  0.239  1.0
  Nb  Nb3  1  0.000  0.492  0.505  1.0
  Nb  Nb4  1  0.000  0.005  0.992  1.0
  O  O5  1  0.000  0.722  0.774  1.0
  O  O6  1  0.000  0.226  0.726  1.0
  O  O7  1  0.000  0.774  0.274  1.0
  O  O8  1  0.000  0.274  0.222  1.0
  O  O9  1  0.500  0.990  0.005  1.0
  O  O10  1  0.500  0.505  0.490  1.0
[/CIF]
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The material structure described by Na2MgNb2O6 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent O(2), two equivalent O(4), and four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. Mg(1) is bonded in a rectangular see-saw-like geometry to one Na(1), two equivalent O(3), and two equivalent O(4) atoms. Nb(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 7-12°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Na(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Nb(1) atoms to form distorted ONa4Nb2 octahedra that share edges with two equivalent O(2)Na4Nb2 octahedra and faces with four equivalent O(4)Na2MgNb2 trigonal bipyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Mg(1), and two equivalent Nb(1) atoms to form distorted ONa2MgNb2 trigonal bipyramids that share corners with three equivalent O(4)Na2MgNb2 trigonal bipyramids,  an edgeedge with one O(4)Na2MgNb2 trigonal bipyramid, and faces with two equivalent O(2)Na4Nb2 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2MgNb2O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.122
_cell_length_b   5.835
_cell_length_c   5.835
_cell_angle_alpha   90.339
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   140.359
_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  0.500  0.404  0.904  1.0
  Na  Na1  1  0.500  0.071  0.571  1.0
  Mg  Mg2  1  0.500  0.739  0.239  1.0
  Nb  Nb3  1  0.000  0.492  0.505  1.0
  Nb  Nb4  1  0.000  0.005  0.992  1.0
  O  O5  1  0.000  0.722  0.774  1.0
  O  O6  1  0.000  0.226  0.726  1.0
  O  O7  1  0.000  0.774  0.274  1.0
  O  O8  1  0.000  0.274  0.222  1.0
  O  O9  1  0.500  0.990  0.005  1.0
  O  O10  1  0.500  0.505  0.490  1.0
[/CIF]
.