The material structure described by Na8MgMn2O8 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form distorted NaO5 square pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(1)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and edges with two equivalent Mn(2)O4 trigonal pyramids. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. In the fifth Na site, Na(5) is bonded in a distorted trigonal non-coplanar geometry to one O(3), one O(4), and one O(5) atom. In the sixth Na site, Na(6) is bonded in a distorted see-saw-like geometry to one O(3), one O(5), one O(6), and one O(7) atom. In the seventh Na site, Na(7) is bonded in a distorted see-saw-like geometry to one O(5), one O(6), one O(7), and one O(8) atom. In the eighth Na site, Na(8) is bonded in a 4-coordinate geometry to one O(1), one O(6), one O(7), and one O(8) atom. Mg(1) is bonded to one O(1), one O(2), one O(6), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Na(1)O5 square pyramid,  a cornercorner with one Mn(1)O4 tetrahedra, corners with three equivalent Mn(2)O4 trigonal pyramids, and  an edgeedge with one Na(1)O5 square pyramid. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form MnO4 tetrahedra that share  a cornercorner with one Na(1)O5 square pyramid and  a cornercorner with one Mg(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form distorted MnO4 trigonal pyramids that share corners with three equivalent Mg(1)O4 tetrahedra and edges with two equivalent Na(1)O5 square pyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(8), one Mg(1), and one Mn(2) atom. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(3), one Na(4), one Mg(1), and one Mn(2) atom to form distorted ONa4MgMn octahedra that share  an edgeedge with one O(5)Na5Mn octahedra, edges with two equivalent O(8)Na4MgMn octahedra, and edges with two equivalent O(4)Na5Mn octahedra. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(2), one Na(3), one Na(4), one Na(5), one Na(6), and one Mn(1) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(3), one Na(4), one Na(5), and one Mn(1) atom to form ONa5Mn octahedra that share  an edgeedge with one O(8)Na4MgMn octahedra, edges with two equivalent O(2)Na4MgMn octahedra, and edges with two equivalent O(5)Na5Mn octahedra. In the fifth O site, O(5) is bonded to one Na(3), one Na(4), one Na(5), one Na(6), one Na(7), and one Mn(1) atom to form distorted ONa5Mn octahedra that share  a cornercorner with one O(8)Na4MgMn octahedra,  an edgeedge with one O(2)Na4MgMn octahedra, and edges with two equivalent O(4)Na5Mn octahedra. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(6), one Na(7), one Na(8), one Mg(1), and one Mn(1) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(6), one Na(7), one Na(8), and one Mn(2) atom. In the eighth O site, O(8) is bonded to one Na(1), one Na(2), one Na(7), one Na(8), one Mg(1), and one Mn(2) atom to form distorted ONa4MgMn octahedra that share  a cornercorner with one O(5)Na5Mn octahedra,  an edgeedge with one O(4)Na5Mn octahedra, and edges with two equivalent O(2)Na4MgMn octahedra. The corner-sharing octahedral tilt angles are 15°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na8MgMn2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.807
_cell_length_b   5.896
_cell_length_c   5.928
_cell_angle_alpha   70.614
_cell_angle_beta   108.252
_cell_angle_gamma   102.901
_symmetry_Int_Tables_number   1
_cell_volume   273.285
_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  0.132  0.002  0.548  1.0
  Na  Na1  1  0.172  0.518  0.054  1.0
  Na  Na2  1  0.307  0.522  0.635  1.0
  Na  Na3  1  0.370  0.988  0.206  1.0
  Na  Na4  1  0.535  0.037  0.686  1.0
  Na  Na5  1  0.682  0.637  0.941  1.0
  Na  Na6  1  0.764  0.976  0.400  1.0
  Na  Na7  1  0.853  0.437  0.756  1.0
  Mg  Mg8  1  0.961  0.431  0.369  1.0
  Mn  Mn9  1  0.520  0.537  0.325  1.0
  Mn  Mn10  1  0.013  0.007  0.002  1.0
  O  O11  1  0.074  0.289  0.739  1.0
  O  O12  1  0.105  0.749  0.290  1.0
  O  O13  1  0.465  0.768  0.010  1.0
  O  O14  1  0.359  0.271  0.416  1.0
  O  O15  1  0.541  0.728  0.532  1.0
  O  O16  1  0.725  0.403  0.355  1.0
  O  O17  1  0.926  0.804  0.799  1.0
  O  O18  1  0.953  0.203  0.170  1.0
[/CIF]
.
The material structure described by Na8MgMn2O8 crystallizes in the triclinic P1 space group. There are eight inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form distorted NaO5 square pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Mn(1)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and edges with two equivalent Mn(2)O4 trigonal pyramids. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the fourth Na site, Na(4) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. In the fifth Na site, Na(5) is bonded in a distorted trigonal non-coplanar geometry to one O(3), one O(4), and one O(5) atom. In the sixth Na site, Na(6) is bonded in a distorted see-saw-like geometry to one O(3), one O(5), one O(6), and one O(7) atom. In the seventh Na site, Na(7) is bonded in a distorted see-saw-like geometry to one O(5), one O(6), one O(7), and one O(8) atom. In the eighth Na site, Na(8) is bonded in a 4-coordinate geometry to one O(1), one O(6), one O(7), and one O(8) atom. Mg(1) is bonded to one O(1), one O(2), one O(6), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Na(1)O5 square pyramid,  a cornercorner with one Mn(1)O4 tetrahedra, corners with three equivalent Mn(2)O4 trigonal pyramids, and  an edgeedge with one Na(1)O5 square pyramid. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form MnO4 tetrahedra that share  a cornercorner with one Na(1)O5 square pyramid and  a cornercorner with one Mg(1)O4 tetrahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form distorted MnO4 trigonal pyramids that share corners with three equivalent Mg(1)O4 tetrahedra and edges with two equivalent Na(1)O5 square pyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(8), one Mg(1), and one Mn(2) atom. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(3), one Na(4), one Mg(1), and one Mn(2) atom to form distorted ONa4MgMn octahedra that share  an edgeedge with one O(5)Na5Mn octahedra, edges with two equivalent O(8)Na4MgMn octahedra, and edges with two equivalent O(4)Na5Mn octahedra. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(2), one Na(3), one Na(4), one Na(5), one Na(6), and one Mn(1) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(3), one Na(4), one Na(5), and one Mn(1) atom to form ONa5Mn octahedra that share  an edgeedge with one O(8)Na4MgMn octahedra, edges with two equivalent O(2)Na4MgMn octahedra, and edges with two equivalent O(5)Na5Mn octahedra. In the fifth O site, O(5) is bonded to one Na(3), one Na(4), one Na(5), one Na(6), one Na(7), and one Mn(1) atom to form distorted ONa5Mn octahedra that share  a cornercorner with one O(8)Na4MgMn octahedra,  an edgeedge with one O(2)Na4MgMn octahedra, and edges with two equivalent O(4)Na5Mn octahedra. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(6), one Na(7), one Na(8), one Mg(1), and one Mn(1) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(6), one Na(7), one Na(8), and one Mn(2) atom. In the eighth O site, O(8) is bonded to one Na(1), one Na(2), one Na(7), one Na(8), one Mg(1), and one Mn(2) atom to form distorted ONa4MgMn octahedra that share  a cornercorner with one O(5)Na5Mn octahedra,  an edgeedge with one O(4)Na5Mn octahedra, and edges with two equivalent O(2)Na4MgMn octahedra. The corner-sharing octahedral tilt angles are 15°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na8MgMn2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.807
_cell_length_b   5.896
_cell_length_c   5.928
_cell_angle_alpha   70.614
_cell_angle_beta   108.252
_cell_angle_gamma   102.901
_symmetry_Int_Tables_number   1
_cell_volume   273.285
_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  0.132  0.002  0.548  1.0
  Na  Na1  1  0.172  0.518  0.054  1.0
  Na  Na2  1  0.307  0.522  0.635  1.0
  Na  Na3  1  0.370  0.988  0.206  1.0
  Na  Na4  1  0.535  0.037  0.686  1.0
  Na  Na5  1  0.682  0.637  0.941  1.0
  Na  Na6  1  0.764  0.976  0.400  1.0
  Na  Na7  1  0.853  0.437  0.756  1.0
  Mg  Mg8  1  0.961  0.431  0.369  1.0
  Mn  Mn9  1  0.520  0.537  0.325  1.0
  Mn  Mn10  1  0.013  0.007  0.002  1.0
  O  O11  1  0.074  0.289  0.739  1.0
  O  O12  1  0.105  0.749  0.290  1.0
  O  O13  1  0.465  0.768  0.010  1.0
  O  O14  1  0.359  0.271  0.416  1.0
  O  O15  1  0.541  0.728  0.532  1.0
  O  O16  1  0.725  0.403  0.355  1.0
  O  O17  1  0.926  0.804  0.799  1.0
  O  O18  1  0.953  0.203  0.170  1.0
[/CIF]
.