The structure described by Na2MgMn4O8 crystallizes in the monoclinic C2/m space group. Na(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra and edges with four equivalent Mn(3)O6 octahedra. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra and edges with four equivalent Mn(3)O6 octahedra. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom to form distorted ONaMgMn3 trigonal bipyramids that share corners with three equivalent O(2)NaMn3 tetrahedra, corners with five equivalent O(1)NaMgMn3 trigonal bipyramids,  an edgeedge with one O(2)NaMn3 tetrahedra, and edges with three equivalent O(1)NaMgMn3 trigonal bipyramids. In the second O site, O(2) is bonded to one Na(1), one Mn(1), and two equivalent Mn(3) atoms to form ONaMn3 tetrahedra that share corners with three equivalent O(2)NaMn3 tetrahedra, corners with six equivalent O(1)NaMgMn3 trigonal bipyramids, and edges with two equivalent O(1)NaMgMn3 trigonal bipyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. is represented by the CIF card [CIF]
data_Na2MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.203
_cell_length_b   6.163
_cell_length_c   5.868
_cell_angle_alpha   61.569
_cell_angle_beta   90.000
_cell_angle_gamma   112.618
_symmetry_Int_Tables_number   1
_cell_volume   177.411
_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  0.904  0.953  0.024  1.0
  Na  Na1  1  0.846  0.547  0.726  1.0
  Mg  Mg2  1  0.375  0.250  0.875  1.0
  Mn  Mn3  1  0.375  0.250  0.375  1.0
  Mn  Mn4  1  0.875  0.250  0.375  1.0
  Mn  Mn5  1  0.375  0.750  0.375  1.0
  Mn  Mn6  1  0.375  0.750  0.875  1.0
  O  O7  1  0.158  0.276  0.129  1.0
  O  O8  1  0.592  0.224  0.154  1.0
  O  O9  1  0.535  0.650  0.175  1.0
  O  O10  1  0.192  0.803  0.098  1.0
  O  O11  1  0.592  0.224  0.621  1.0
  O  O12  1  0.158  0.276  0.596  1.0
  O  O13  1  0.558  0.697  0.652  1.0
  O  O14  1  0.215  0.850  0.575  1.0
[/CIF]
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The structure described by Na2MgMn4O8 crystallizes in the monoclinic C2/m space group. Na(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(1) atoms. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra and edges with four equivalent Mn(3)O6 octahedra. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra and edges with four equivalent Mn(3)O6 octahedra. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mg(1), one Mn(1), one Mn(2), and one Mn(3) atom to form distorted ONaMgMn3 trigonal bipyramids that share corners with three equivalent O(2)NaMn3 tetrahedra, corners with five equivalent O(1)NaMgMn3 trigonal bipyramids,  an edgeedge with one O(2)NaMn3 tetrahedra, and edges with three equivalent O(1)NaMgMn3 trigonal bipyramids. In the second O site, O(2) is bonded to one Na(1), one Mn(1), and two equivalent Mn(3) atoms to form ONaMn3 tetrahedra that share corners with three equivalent O(2)NaMn3 tetrahedra, corners with six equivalent O(1)NaMgMn3 trigonal bipyramids, and edges with two equivalent O(1)NaMgMn3 trigonal bipyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. is represented by the CIF card [CIF]
data_Na2MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.203
_cell_length_b   6.163
_cell_length_c   5.868
_cell_angle_alpha   61.569
_cell_angle_beta   90.000
_cell_angle_gamma   112.618
_symmetry_Int_Tables_number   1
_cell_volume   177.411
_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  0.904  0.953  0.024  1.0
  Na  Na1  1  0.846  0.547  0.726  1.0
  Mg  Mg2  1  0.375  0.250  0.875  1.0
  Mn  Mn3  1  0.375  0.250  0.375  1.0
  Mn  Mn4  1  0.875  0.250  0.375  1.0
  Mn  Mn5  1  0.375  0.750  0.375  1.0
  Mn  Mn6  1  0.375  0.750  0.875  1.0
  O  O7  1  0.158  0.276  0.129  1.0
  O  O8  1  0.592  0.224  0.154  1.0
  O  O9  1  0.535  0.650  0.175  1.0
  O  O10  1  0.192  0.803  0.098  1.0
  O  O11  1  0.592  0.224  0.621  1.0
  O  O12  1  0.158  0.276  0.596  1.0
  O  O13  1  0.558  0.697  0.652  1.0
  O  O14  1  0.215  0.850  0.575  1.0
[/CIF]
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