The material structure described by Na4FeO4 crystallizes in the triclinic P-1 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(1), one O(3), one O(4), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the third Na site, Na(3) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Fe(1)O4 tetrahedra,  an edgeedge with one Fe(1)O4 tetrahedra, and edges with two equivalent Na(3)O5 trigonal bipyramids. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted FeO4 tetrahedra that share corners with three equivalent Na(3)O5 trigonal bipyramids and  an edgeedge with one Na(3)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(4), and one Fe(1) atom. In the second O site, O(2) is bonded to one Na(4), two equivalent Na(1), two equivalent Na(3), and one Fe(1) atom to form a mixture of edge and corner-sharing ONa5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-23°. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(4), two equivalent Na(2), and one Fe(1) atom to form a mixture of edge and corner-sharing ONa5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-23°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), and one Fe(1) atom. is represented by the CIF card [CIF]
data_Na4FeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.708
_cell_length_b   5.701
_cell_length_c   8.089
_cell_angle_alpha   88.465
_cell_angle_beta   107.388
_cell_angle_gamma   110.365
_symmetry_Int_Tables_number   1
_cell_volume   234.615
_cell_formula_units_Z   2
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  0.406  0.210  0.368  1.0
  Na  Na1  1  0.594  0.790  0.632  1.0
  Na  Na2  1  0.796  0.740  0.017  1.0
  Na  Na3  1  0.204  0.260  0.983  1.0
  Na  Na4  1  0.954  0.723  0.432  1.0
  Na  Na5  1  0.046  0.277  0.568  1.0
  Na  Na6  1  0.754  0.231  0.166  1.0
  Na  Na7  1  0.246  0.769  0.834  1.0
  Fe  Fe8  1  0.589  0.280  0.748  1.0
  Fe  Fe9  1  0.411  0.720  0.252  1.0
  O  O10  1  0.243  0.899  0.110  1.0
  O  O11  1  0.757  0.101  0.890  1.0
  O  O12  1  0.690  0.971  0.383  1.0
  O  O13  1  0.310  0.029  0.617  1.0
  O  O14  1  0.430  0.475  0.798  1.0
  O  O15  1  0.570  0.525  0.202  1.0
  O  O16  1  0.168  0.495  0.329  1.0
  O  O17  1  0.832  0.505  0.671  1.0
[/CIF]
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The material structure described by Na4FeO4 crystallizes in the triclinic P-1 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(1), one O(3), one O(4), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the third Na site, Na(3) is bonded to one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted NaO5 trigonal bipyramids that share corners with three equivalent Fe(1)O4 tetrahedra,  an edgeedge with one Fe(1)O4 tetrahedra, and edges with two equivalent Na(3)O5 trigonal bipyramids. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(4), and two equivalent O(1) atoms. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted FeO4 tetrahedra that share corners with three equivalent Na(3)O5 trigonal bipyramids and  an edgeedge with one Na(3)O5 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(4), and one Fe(1) atom. In the second O site, O(2) is bonded to one Na(4), two equivalent Na(1), two equivalent Na(3), and one Fe(1) atom to form a mixture of edge and corner-sharing ONa5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-23°. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(4), two equivalent Na(2), and one Fe(1) atom to form a mixture of edge and corner-sharing ONa5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-23°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Na(1), one Na(4), two equivalent Na(3), and one Fe(1) atom. is represented by the CIF card [CIF]
data_Na4FeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.708
_cell_length_b   5.701
_cell_length_c   8.089
_cell_angle_alpha   88.465
_cell_angle_beta   107.388
_cell_angle_gamma   110.365
_symmetry_Int_Tables_number   1
_cell_volume   234.615
_cell_formula_units_Z   2
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  0.406  0.210  0.368  1.0
  Na  Na1  1  0.594  0.790  0.632  1.0
  Na  Na2  1  0.796  0.740  0.017  1.0
  Na  Na3  1  0.204  0.260  0.983  1.0
  Na  Na4  1  0.954  0.723  0.432  1.0
  Na  Na5  1  0.046  0.277  0.568  1.0
  Na  Na6  1  0.754  0.231  0.166  1.0
  Na  Na7  1  0.246  0.769  0.834  1.0
  Fe  Fe8  1  0.589  0.280  0.748  1.0
  Fe  Fe9  1  0.411  0.720  0.252  1.0
  O  O10  1  0.243  0.899  0.110  1.0
  O  O11  1  0.757  0.101  0.890  1.0
  O  O12  1  0.690  0.971  0.383  1.0
  O  O13  1  0.310  0.029  0.617  1.0
  O  O14  1  0.430  0.475  0.798  1.0
  O  O15  1  0.570  0.525  0.202  1.0
  O  O16  1  0.168  0.495  0.329  1.0
  O  O17  1  0.832  0.505  0.671  1.0
[/CIF]
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