The crystal structure described by Na2MgFe4O7 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to 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 5-coordinate geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(7) atom to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  a cornercorner with one Fe(1)O4 trigonal pyramid, corners with two equivalent Fe(2)O4 trigonal pyramids,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and  a faceface with one Fe(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 15-49°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form distorted FeO4 trigonal pyramids that share corners with three equivalent Fe(3)O6 octahedra, corners with three equivalent Fe(4)O6 octahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  a cornercorner with one Fe(2)O4 trigonal pyramid, and  a faceface with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 60-85°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form distorted FeO4 trigonal pyramids that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(1)O4 trigonal pyramid,  an edgeedge with one Fe(3)O6 octahedra, and  an edgeedge with one Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-41°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(2)O4 trigonal pyramid, corners with three equivalent Fe(1)O4 trigonal pyramids, edges with three equivalent Fe(4)O6 octahedra,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O4 trigonal pyramid. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(2)O4 trigonal pyramid, corners with three equivalent Fe(1)O4 trigonal pyramids, edges with three equivalent Fe(3)O6 octahedra,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O4 trigonal pyramid. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom to form distorted OMgFe3 tetrahedra that share corners with two equivalent O(5)Na2Fe3 square pyramids and corners with two equivalent O(3)Na2MgFe2 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Mg(1), one Fe(1), and one Fe(2) atom to form ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(5)Na2Fe3 square pyramid, corners with two equivalent O(1)MgFe3 tetrahedra, and  an edgeedge with one O(5)Na2Fe3 square pyramid. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Fe(2), one Fe(3), and one Fe(4) atom to form distorted ONa2Fe3 square pyramids that share corners with two equivalent O(1)MgFe3 tetrahedra,  a cornercorner with one O(3)Na2MgFe2 trigonal bipyramid, and  an edgeedge with one O(3)Na2MgFe2 trigonal bipyramid. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. is represented by the CIF file [CIF]
data_Na2MgFe4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.621
_cell_length_b   5.826
_cell_length_c   5.919
_cell_angle_alpha   85.729
_cell_angle_beta   92.634
_cell_angle_gamma   120.906
_symmetry_Int_Tables_number   1
_cell_volume   165.861
_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  0.535  0.817  0.968  1.0
  Na  Na1  1  0.466  0.283  0.967  1.0
  Mg  Mg2  1  0.003  0.351  0.079  1.0
  Fe  Fe3  1  0.995  0.973  0.336  1.0
  Fe  Fe4  1  0.000  0.816  0.766  1.0
  Fe  Fe5  1  0.332  0.671  0.491  1.0
  Fe  Fe6  1  0.663  0.339  0.489  1.0
  O  O7  1  0.998  0.616  0.293  1.0
  O  O8  1  0.002  0.467  0.740  1.0
  O  O9  1  0.002  0.029  0.992  1.0
  O  O10  1  0.341  0.401  0.290  1.0
  O  O11  1  0.605  0.608  0.665  1.0
  O  O12  1  0.392  0.003  0.660  1.0
  O  O13  1  0.666  0.062  0.292  1.0
[/CIF]
.
The crystal structure described by Na2MgFe4O7 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to 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 5-coordinate geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(7) atom to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra,  a cornercorner with one Fe(1)O4 trigonal pyramid, corners with two equivalent Fe(2)O4 trigonal pyramids,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and  a faceface with one Fe(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 15-49°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form distorted FeO4 trigonal pyramids that share corners with three equivalent Fe(3)O6 octahedra, corners with three equivalent Fe(4)O6 octahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  a cornercorner with one Fe(2)O4 trigonal pyramid, and  a faceface with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 60-85°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form distorted FeO4 trigonal pyramids that share  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(1)O4 trigonal pyramid,  an edgeedge with one Fe(3)O6 octahedra, and  an edgeedge with one Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-41°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(2)O4 trigonal pyramid, corners with three equivalent Fe(1)O4 trigonal pyramids, edges with three equivalent Fe(4)O6 octahedra,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O4 trigonal pyramid. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O5 trigonal bipyramids,  a cornercorner with one Fe(2)O4 trigonal pyramid, corners with three equivalent Fe(1)O4 trigonal pyramids, edges with three equivalent Fe(3)O6 octahedra,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O4 trigonal pyramid. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom to form distorted OMgFe3 tetrahedra that share corners with two equivalent O(5)Na2Fe3 square pyramids and corners with two equivalent O(3)Na2MgFe2 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Mg(1), one Fe(1), and one Fe(2) atom to form ONa2MgFe2 trigonal bipyramids that share  a cornercorner with one O(5)Na2Fe3 square pyramid, corners with two equivalent O(1)MgFe3 tetrahedra, and  an edgeedge with one O(5)Na2Fe3 square pyramid. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Fe(2), one Fe(3), and one Fe(4) atom to form distorted ONa2Fe3 square pyramids that share corners with two equivalent O(1)MgFe3 tetrahedra,  a cornercorner with one O(3)Na2MgFe2 trigonal bipyramid, and  an edgeedge with one O(3)Na2MgFe2 trigonal bipyramid. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. is represented by the CIF file [CIF]
data_Na2MgFe4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.621
_cell_length_b   5.826
_cell_length_c   5.919
_cell_angle_alpha   85.729
_cell_angle_beta   92.634
_cell_angle_gamma   120.906
_symmetry_Int_Tables_number   1
_cell_volume   165.861
_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  0.535  0.817  0.968  1.0
  Na  Na1  1  0.466  0.283  0.967  1.0
  Mg  Mg2  1  0.003  0.351  0.079  1.0
  Fe  Fe3  1  0.995  0.973  0.336  1.0
  Fe  Fe4  1  0.000  0.816  0.766  1.0
  Fe  Fe5  1  0.332  0.671  0.491  1.0
  Fe  Fe6  1  0.663  0.339  0.489  1.0
  O  O7  1  0.998  0.616  0.293  1.0
  O  O8  1  0.002  0.467  0.740  1.0
  O  O9  1  0.002  0.029  0.992  1.0
  O  O10  1  0.341  0.401  0.290  1.0
  O  O11  1  0.605  0.608  0.665  1.0
  O  O12  1  0.392  0.003  0.660  1.0
  O  O13  1  0.666  0.062  0.292  1.0
[/CIF]
.