The compound described by Na4MgMn4O8 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(5) atoms. In the second Na site, Na(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(7) atoms to form NaO5 square pyramids that share corners with two equivalent Mn(3)O5 square pyramids, edges with two equivalent Na(2)O5 square pyramids, and edges with two equivalent Mn(2)O5 square pyramids. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(2), and two equivalent O(6) atoms. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(8) atoms. Mg(1) is bonded to one O(1), one O(5), and two equivalent O(6) atoms to form MgO4 tetrahedra that share corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(5) atoms. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Mn(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 tetrahedra. In the third Mn site, Mn(3) is bonded to one O(7), two equivalent O(3), and two equivalent O(8) atoms to form MnO5 square pyramids that share corners with two equivalent Na(2)O5 square pyramids and edges with two equivalent Mn(3)O5 square pyramids. In the fourth Mn site, Mn(4) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(4), and two equivalent O(7) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(4), two equivalent Na(1), one Mg(1), and two equivalent Mn(1) atoms to form distorted ONa3MgMn2 octahedra that share corners with four equivalent O(3)Na3Mn2 trigonal bipyramids and edges with two equivalent O(1)Na3MgMn2 octahedra. In the second O site, O(2) is bonded to one Na(2), two equivalent Na(3), and two equivalent Mn(2) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with two equivalent O(7)Na2Mn3 trigonal bipyramids and edges with two equivalent O(2)Na3Mn2 trigonal bipyramids. In the third O site, O(3) is bonded to one Na(1), two equivalent Na(4), and two equivalent Mn(3) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with four equivalent O(1)Na3MgMn2 octahedra, corners with two equivalent O(7)Na2Mn3 trigonal bipyramids, and edges with two equivalent O(3)Na3Mn2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-76°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(3), two equivalent Na(2), one Mn(2), and two equivalent Mn(4) atoms. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Mg(1), and two equivalent Mn(1) atoms. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to two equivalent Na(3), two equivalent Mg(1), and two equivalent Mn(2) atoms. In the seventh O site, O(7) is bonded to two equivalent Na(2), one Mn(3), and two equivalent Mn(4) atoms to form distorted ONa2Mn3 trigonal bipyramids that share corners with two equivalent O(2)Na3Mn2 trigonal bipyramids, corners with two equivalent O(3)Na3Mn2 trigonal bipyramids, and edges with two equivalent O(7)Na2Mn3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to two equivalent Na(4), one Mn(4), and two equivalent Mn(3) atoms. is represented by the CIF card [CIF]
data_Na4MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.005
_cell_length_b   5.807
_cell_length_c   12.904
_cell_angle_alpha   86.872
_cell_angle_beta   90.001
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   224.847
_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  0.250  0.548  0.212  1.0
  Na  Na1  1  0.250  0.027  0.616  1.0
  Na  Na2  1  0.750  0.404  0.838  1.0
  Na  Na3  1  0.750  0.967  0.355  1.0
  Mg  Mg4  1  0.750  0.646  0.024  1.0
  Mn  Mn5  1  0.250  0.096  0.114  1.0
  Mn  Mn6  1  0.750  0.907  0.824  1.0
  Mn  Mn7  1  0.750  0.456  0.417  1.0
  Mn  Mn8  1  0.250  0.525  0.623  1.0
  O  O9  1  0.750  0.848  0.147  1.0
  O  O10  1  0.250  0.132  0.793  1.0
  O  O11  1  0.250  0.279  0.358  1.0
  O  O12  1  0.750  0.706  0.684  1.0
  O  O13  1  0.750  0.338  0.098  1.0
  O  O14  1  0.250  0.697  0.924  1.0
  O  O15  1  0.750  0.329  0.573  1.0
  O  O16  1  0.250  0.678  0.438  1.0
[/CIF]
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The compound described by Na4MgMn4O8 crystallizes in the monoclinic Pm space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(5) atoms. In the second Na site, Na(2) is bonded to one O(2), two equivalent O(4), and two equivalent O(7) atoms to form NaO5 square pyramids that share corners with two equivalent Mn(3)O5 square pyramids, edges with two equivalent Na(2)O5 square pyramids, and edges with two equivalent Mn(2)O5 square pyramids. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(2), and two equivalent O(6) atoms. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(8) atoms. Mg(1) is bonded to one O(1), one O(5), and two equivalent O(6) atoms to form MgO4 tetrahedra that share corners with two equivalent Mn(2)O5 square pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(5) atoms. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Mn(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 tetrahedra. In the third Mn site, Mn(3) is bonded to one O(7), two equivalent O(3), and two equivalent O(8) atoms to form MnO5 square pyramids that share corners with two equivalent Na(2)O5 square pyramids and edges with two equivalent Mn(3)O5 square pyramids. In the fourth Mn site, Mn(4) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(4), and two equivalent O(7) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(4), two equivalent Na(1), one Mg(1), and two equivalent Mn(1) atoms to form distorted ONa3MgMn2 octahedra that share corners with four equivalent O(3)Na3Mn2 trigonal bipyramids and edges with two equivalent O(1)Na3MgMn2 octahedra. In the second O site, O(2) is bonded to one Na(2), two equivalent Na(3), and two equivalent Mn(2) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with two equivalent O(7)Na2Mn3 trigonal bipyramids and edges with two equivalent O(2)Na3Mn2 trigonal bipyramids. In the third O site, O(3) is bonded to one Na(1), two equivalent Na(4), and two equivalent Mn(3) atoms to form distorted ONa3Mn2 trigonal bipyramids that share corners with four equivalent O(1)Na3MgMn2 octahedra, corners with two equivalent O(7)Na2Mn3 trigonal bipyramids, and edges with two equivalent O(3)Na3Mn2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 45-76°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(3), two equivalent Na(2), one Mn(2), and two equivalent Mn(4) atoms. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to two equivalent Na(1), one Mg(1), and two equivalent Mn(1) atoms. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to two equivalent Na(3), two equivalent Mg(1), and two equivalent Mn(2) atoms. In the seventh O site, O(7) is bonded to two equivalent Na(2), one Mn(3), and two equivalent Mn(4) atoms to form distorted ONa2Mn3 trigonal bipyramids that share corners with two equivalent O(2)Na3Mn2 trigonal bipyramids, corners with two equivalent O(3)Na3Mn2 trigonal bipyramids, and edges with two equivalent O(7)Na2Mn3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to two equivalent Na(4), one Mn(4), and two equivalent Mn(3) atoms. is represented by the CIF card [CIF]
data_Na4MgMn4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.005
_cell_length_b   5.807
_cell_length_c   12.904
_cell_angle_alpha   86.872
_cell_angle_beta   90.001
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   224.847
_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  0.250  0.548  0.212  1.0
  Na  Na1  1  0.250  0.027  0.616  1.0
  Na  Na2  1  0.750  0.404  0.838  1.0
  Na  Na3  1  0.750  0.967  0.355  1.0
  Mg  Mg4  1  0.750  0.646  0.024  1.0
  Mn  Mn5  1  0.250  0.096  0.114  1.0
  Mn  Mn6  1  0.750  0.907  0.824  1.0
  Mn  Mn7  1  0.750  0.456  0.417  1.0
  Mn  Mn8  1  0.250  0.525  0.623  1.0
  O  O9  1  0.750  0.848  0.147  1.0
  O  O10  1  0.250  0.132  0.793  1.0
  O  O11  1  0.250  0.279  0.358  1.0
  O  O12  1  0.750  0.706  0.684  1.0
  O  O13  1  0.750  0.338  0.098  1.0
  O  O14  1  0.250  0.697  0.924  1.0
  O  O15  1  0.750  0.329  0.573  1.0
  O  O16  1  0.250  0.678  0.438  1.0
[/CIF]
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