The material described by Na4Mg(Fe2O5)2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(5), one O(6), and one O(9) atom. In the third Na site, Na(3) is bonded in a 3-coordinate geometry to one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(7), one O(8), and one O(9) atom. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(10), one O(2), and one O(9) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(4), one O(6), and one O(9) atom to form FeO6 octahedra that share corners with four equivalent Fe(3)O6 octahedra,  a cornercorner with one Fe(2)O4 tetrahedra, and  a cornercorner with one Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 6-10°. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with two equivalent Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-49°. In the third Fe site, Fe(3) is bonded to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O4 tetrahedra, and  a cornercorner with one Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 6-10°. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom to form distorted ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(8)Na2Fe2 tetrahedra,  an edgeedge with one O(10)Na2MgFe2 trigonal bipyramid, and  a faceface with one O(10)Na2MgFe2 trigonal bipyramid. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Fe(2), and one Fe(4) atom to form distorted ONa2Fe2 tetrahedra that share corners with two equivalent O(8)Na2Fe2 tetrahedra,  a cornercorner with one O(1)Na2MgFe2 trigonal bipyramid, and  a cornercorner with one O(10)Na2MgFe2 trigonal bipyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Fe(1), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Fe(2), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Fe(1), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Fe(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Fe(2), and one Fe(4) atom to form distorted ONa2Fe2 tetrahedra that share corners with two equivalent O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(1)Na2MgFe2 trigonal bipyramid, and  a cornercorner with one O(10)Na2MgFe2 trigonal bipyramid. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom. In the tenth O site, O(10) is bonded to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom to form distorted ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(8)Na2Fe2 tetrahedra,  an edgeedge with one O(1)Na2MgFe2 trigonal bipyramid, and  a faceface with one O(1)Na2MgFe2 trigonal bipyramid. is represented by the CIF file [CIF]
data_Na4Mg(Fe2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.736
_cell_length_b   7.916
_cell_length_c   5.910
_cell_angle_alpha   68.886
_cell_angle_beta   89.973
_cell_angle_gamma   68.747
_symmetry_Int_Tables_number   1
_cell_volume   230.670
_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  0.570  0.583  0.383  1.0
  Na  Na1  1  0.910  0.193  0.439  1.0
  Na  Na2  1  0.151  0.419  0.615  1.0
  Na  Na3  1  0.103  0.808  0.561  1.0
  Mg  Mg4  1  0.549  0.001  1.000  1.0
  Fe  Fe5  1  0.039  1.000  1.000  1.0
  Fe  Fe6  1  0.189  0.501  0.120  1.0
  Fe  Fe7  1  0.535  1.000  0.500  1.0
  Fe  Fe8  1  0.691  0.499  0.880  1.0
  O  O9  1  0.780  0.025  0.227  1.0
  O  O10  1  0.300  0.005  0.239  1.0
  O  O11  1  0.863  0.490  0.158  1.0
  O  O12  1  0.174  0.712  0.199  1.0
  O  O13  1  0.422  0.291  0.387  1.0
  O  O14  1  0.887  0.287  0.801  1.0
  O  O15  1  0.715  0.709  0.614  1.0
  O  O16  1  0.353  0.510  0.842  1.0
  O  O17  1  0.306  0.994  0.762  1.0
  O  O18  1  0.804  0.975  0.773  1.0
[/CIF]
.
The material described by Na4Mg(Fe2O5)2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(5), one O(6), and one O(9) atom. In the third Na site, Na(3) is bonded in a 3-coordinate geometry to one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(4), one O(7), one O(8), and one O(9) atom. Mg(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(10), one O(2), and one O(9) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(4), one O(6), and one O(9) atom to form FeO6 octahedra that share corners with four equivalent Fe(3)O6 octahedra,  a cornercorner with one Fe(2)O4 tetrahedra, and  a cornercorner with one Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 6-10°. In the second Fe site, Fe(2) is bonded to one O(3), one O(4), one O(5), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with two equivalent Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-49°. In the third Fe site, Fe(3) is bonded to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O4 tetrahedra, and  a cornercorner with one Fe(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 6-10°. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom to form distorted ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(8)Na2Fe2 tetrahedra,  an edgeedge with one O(10)Na2MgFe2 trigonal bipyramid, and  a faceface with one O(10)Na2MgFe2 trigonal bipyramid. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Fe(2), and one Fe(4) atom to form distorted ONa2Fe2 tetrahedra that share corners with two equivalent O(8)Na2Fe2 tetrahedra,  a cornercorner with one O(1)Na2MgFe2 trigonal bipyramid, and  a cornercorner with one O(10)Na2MgFe2 trigonal bipyramid. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Fe(1), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Fe(2), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Fe(1), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Fe(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Fe(2), and one Fe(4) atom to form distorted ONa2Fe2 tetrahedra that share corners with two equivalent O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(1)Na2MgFe2 trigonal bipyramid, and  a cornercorner with one O(10)Na2MgFe2 trigonal bipyramid. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom. In the tenth O site, O(10) is bonded to one Na(2), one Na(4), one Mg(1), one Fe(1), and one Fe(3) atom to form distorted ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(3)Na2Fe2 tetrahedra,  a cornercorner with one O(8)Na2Fe2 tetrahedra,  an edgeedge with one O(1)Na2MgFe2 trigonal bipyramid, and  a faceface with one O(1)Na2MgFe2 trigonal bipyramid. is represented by the CIF file [CIF]
data_Na4Mg(Fe2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.736
_cell_length_b   7.916
_cell_length_c   5.910
_cell_angle_alpha   68.886
_cell_angle_beta   89.973
_cell_angle_gamma   68.747
_symmetry_Int_Tables_number   1
_cell_volume   230.670
_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  0.570  0.583  0.383  1.0
  Na  Na1  1  0.910  0.193  0.439  1.0
  Na  Na2  1  0.151  0.419  0.615  1.0
  Na  Na3  1  0.103  0.808  0.561  1.0
  Mg  Mg4  1  0.549  0.001  1.000  1.0
  Fe  Fe5  1  0.039  1.000  1.000  1.0
  Fe  Fe6  1  0.189  0.501  0.120  1.0
  Fe  Fe7  1  0.535  1.000  0.500  1.0
  Fe  Fe8  1  0.691  0.499  0.880  1.0
  O  O9  1  0.780  0.025  0.227  1.0
  O  O10  1  0.300  0.005  0.239  1.0
  O  O11  1  0.863  0.490  0.158  1.0
  O  O12  1  0.174  0.712  0.199  1.0
  O  O13  1  0.422  0.291  0.387  1.0
  O  O14  1  0.887  0.287  0.801  1.0
  O  O15  1  0.715  0.709  0.614  1.0
  O  O16  1  0.353  0.510  0.842  1.0
  O  O17  1  0.306  0.994  0.762  1.0
  O  O18  1  0.804  0.975  0.773  1.0
[/CIF]
.