The structure described by NaMgMn4O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form NaO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra and edges with four equivalent Mn(2)O6 octahedra. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(3), one O(6), and two equivalent O(2) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Na(1)O6 octahedra and edges with four equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted MnO6 octahedra that share edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) 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  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(4)NaMn3 trigonal pyramid,  an edgeedge with one O(6)MgMn3 tetrahedra, edges with two equivalent O(2)NaMgMn3 trigonal bipyramids, and  an edgeedge with one O(4)NaMn3 trigonal pyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Mn(3), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted ONaMn3 trigonal pyramids that share corners with two equivalent O(6)MgMn3 tetrahedra, corners with two equivalent O(2)NaMgMn3 trigonal bipyramids, and edges with two equivalent O(2)NaMgMn3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Na(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms to form OMgMn3 tetrahedra that share corners with two equivalent O(2)NaMgMn3 trigonal bipyramids, corners with two equivalent O(4)NaMn3 trigonal pyramids, and edges with two equivalent O(2)NaMgMn3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.209
_cell_length_b   6.209
_cell_length_c   6.343
_cell_angle_alpha   86.481
_cell_angle_beta   119.071
_cell_angle_gamma   124.498
_symmetry_Int_Tables_number   1
_cell_volume   168.174
_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  0.507  0.995  0.502  1.0
  Mg  Mg1  1  0.230  0.325  0.555  1.0
  Mn  Mn2  1  0.000  0.995  0.995  1.0
  Mn  Mn3  1  0.987  0.503  0.988  1.0
  Mn  Mn4  1  0.484  0.000  0.988  1.0
  Mn  Mn5  1  0.526  0.528  0.054  1.0
  O  O6  1  0.029  0.785  0.814  1.0
  O  O7  1  0.063  0.257  0.793  1.0
  O  O8  1  0.533  0.250  0.782  1.0
  O  O9  1  0.536  0.731  0.793  1.0
  O  O10  1  0.437  0.751  0.188  1.0
  O  O11  1  0.449  0.241  0.211  1.0
  O  O12  1  0.957  0.220  0.176  1.0
  O  O13  1  0.971  0.762  0.211  1.0
[/CIF]
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The structure described by NaMgMn4O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form NaO6 octahedra that share edges with two equivalent Mn(1)O6 octahedra and edges with four equivalent Mn(2)O6 octahedra. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(3), one O(6), and two equivalent O(2) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form MnO6 octahedra that share edges with two equivalent Na(1)O6 octahedra and edges with four equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted MnO6 octahedra that share edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the second O site, O(2) 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  a cornercorner with one O(6)MgMn3 tetrahedra,  a cornercorner with one O(4)NaMn3 trigonal pyramid,  an edgeedge with one O(6)MgMn3 tetrahedra, edges with two equivalent O(2)NaMgMn3 trigonal bipyramids, and  an edgeedge with one O(4)NaMn3 trigonal pyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Mn(3), and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted ONaMn3 trigonal pyramids that share corners with two equivalent O(6)MgMn3 tetrahedra, corners with two equivalent O(2)NaMgMn3 trigonal bipyramids, and edges with two equivalent O(2)NaMgMn3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Na(1), one Mn(1), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Mn(1), and two equivalent Mn(2) atoms to form OMgMn3 tetrahedra that share corners with two equivalent O(2)NaMgMn3 trigonal bipyramids, corners with two equivalent O(4)NaMn3 trigonal pyramids, and edges with two equivalent O(2)NaMgMn3 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.209
_cell_length_b   6.209
_cell_length_c   6.343
_cell_angle_alpha   86.481
_cell_angle_beta   119.071
_cell_angle_gamma   124.498
_symmetry_Int_Tables_number   1
_cell_volume   168.174
_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  0.507  0.995  0.502  1.0
  Mg  Mg1  1  0.230  0.325  0.555  1.0
  Mn  Mn2  1  0.000  0.995  0.995  1.0
  Mn  Mn3  1  0.987  0.503  0.988  1.0
  Mn  Mn4  1  0.484  0.000  0.988  1.0
  Mn  Mn5  1  0.526  0.528  0.054  1.0
  O  O6  1  0.029  0.785  0.814  1.0
  O  O7  1  0.063  0.257  0.793  1.0
  O  O8  1  0.533  0.250  0.782  1.0
  O  O9  1  0.536  0.731  0.793  1.0
  O  O10  1  0.437  0.751  0.188  1.0
  O  O11  1  0.449  0.241  0.211  1.0
  O  O12  1  0.957  0.220  0.176  1.0
  O  O13  1  0.971  0.762  0.211  1.0
[/CIF]
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