The material structure described by Na(FeO2)2 crystallizes in the monoclinic P2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form edge-sharing FeO6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. In the third Fe site, Fe(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Fe(2), and two equivalent Fe(1) atoms to form ONa2Fe3 trigonal bipyramids that share corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(3)NaFe3 trigonal pyramids, corners with two equivalent O(4)NaFe3 trigonal pyramids,  an edgeedge with one O(1)Na2Fe3 trigonal bipyramid, edges with three equivalent O(2)Na2Fe3 trigonal bipyramids, edges with two equivalent O(3)NaFe3 trigonal pyramids, and edges with two equivalent O(4)NaFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Fe(3), and two equivalent Fe(1) atoms to form ONa2Fe3 trigonal bipyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with three equivalent O(2)Na2Fe3 trigonal bipyramids, corners with two equivalent O(3)NaFe3 trigonal pyramids, corners with two equivalent O(4)NaFe3 trigonal pyramids,  an edgeedge with one O(2)Na2Fe3 trigonal bipyramid, edges with three equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(3)NaFe3 trigonal pyramids, and edges with two equivalent O(4)NaFe3 trigonal pyramids. In the third O site, O(3) is bonded to one Na(2), one Fe(1), one Fe(2), and one Fe(3) atom to form distorted ONaFe3 trigonal pyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(3)NaFe3 trigonal pyramids, corners with three equivalent O(4)NaFe3 trigonal pyramids, edges with two equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(2)Na2Fe3 trigonal bipyramids, and  an edgeedge with one O(4)NaFe3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Fe(1), one Fe(2), and one Fe(3) atom to form ONaFe3 trigonal pyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(3)NaFe3 trigonal pyramids, corners with three equivalent O(4)NaFe3 trigonal pyramids, edges with two equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(2)Na2Fe3 trigonal bipyramids, and  an edgeedge with one O(3)NaFe3 trigonal pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   5.976
_cell_length_c   13.014
_cell_angle_alpha   62.786
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   356.012
_cell_formula_units_Z   4
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  0.970  0.500  0.250  1.0
  Na  Na1  1  0.645  0.000  0.750  1.0
  Na  Na2  1  0.355  0.000  0.250  1.0
  Na  Na3  1  0.030  0.500  0.750  1.0
  Fe  Fe4  1  0.999  0.240  0.008  1.0
  Fe  Fe5  1  0.001  0.760  0.992  1.0
  Fe  Fe6  1  0.999  0.760  0.492  1.0
  Fe  Fe7  1  0.001  0.240  0.508  1.0
  Fe  Fe8  1  0.500  0.500  0.000  1.0
  Fe  Fe9  1  0.500  0.000  0.000  1.0
  Fe  Fe10  1  0.500  0.500  0.500  1.0
  Fe  Fe11  1  0.500  0.000  0.500  1.0
  O  O12  1  0.826  0.413  0.592  1.0
  O  O13  1  0.835  0.097  0.907  1.0
  O  O14  1  0.835  0.903  0.593  1.0
  O  O15  1  0.826  0.587  0.908  1.0
  O  O16  1  0.658  0.169  0.090  1.0
  O  O17  1  0.658  0.831  0.410  1.0
  O  O18  1  0.676  0.659  0.088  1.0
  O  O19  1  0.676  0.341  0.412  1.0
  O  O20  1  0.324  0.659  0.588  1.0
  O  O21  1  0.324  0.341  0.912  1.0
  O  O22  1  0.342  0.169  0.590  1.0
  O  O23  1  0.342  0.831  0.910  1.0
  O  O24  1  0.174  0.587  0.408  1.0
  O  O25  1  0.165  0.097  0.407  1.0
  O  O26  1  0.165  0.903  0.093  1.0
  O  O27  1  0.174  0.413  0.092  1.0
[/CIF]
.
The material structure described by Na(FeO2)2 crystallizes in the monoclinic P2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form edge-sharing FeO6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. In the third Fe site, Fe(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Fe(2), and two equivalent Fe(1) atoms to form ONa2Fe3 trigonal bipyramids that share corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(3)NaFe3 trigonal pyramids, corners with two equivalent O(4)NaFe3 trigonal pyramids,  an edgeedge with one O(1)Na2Fe3 trigonal bipyramid, edges with three equivalent O(2)Na2Fe3 trigonal bipyramids, edges with two equivalent O(3)NaFe3 trigonal pyramids, and edges with two equivalent O(4)NaFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Fe(3), and two equivalent Fe(1) atoms to form ONa2Fe3 trigonal bipyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with three equivalent O(2)Na2Fe3 trigonal bipyramids, corners with two equivalent O(3)NaFe3 trigonal pyramids, corners with two equivalent O(4)NaFe3 trigonal pyramids,  an edgeedge with one O(2)Na2Fe3 trigonal bipyramid, edges with three equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(3)NaFe3 trigonal pyramids, and edges with two equivalent O(4)NaFe3 trigonal pyramids. In the third O site, O(3) is bonded to one Na(2), one Fe(1), one Fe(2), and one Fe(3) atom to form distorted ONaFe3 trigonal pyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(3)NaFe3 trigonal pyramids, corners with three equivalent O(4)NaFe3 trigonal pyramids, edges with two equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(2)Na2Fe3 trigonal bipyramids, and  an edgeedge with one O(4)NaFe3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Fe(1), one Fe(2), and one Fe(3) atom to form ONaFe3 trigonal pyramids that share corners with two equivalent O(1)Na2Fe3 trigonal bipyramids, corners with two equivalent O(2)Na2Fe3 trigonal bipyramids, corners with three equivalent O(3)NaFe3 trigonal pyramids, corners with three equivalent O(4)NaFe3 trigonal pyramids, edges with two equivalent O(1)Na2Fe3 trigonal bipyramids, edges with two equivalent O(2)Na2Fe3 trigonal bipyramids, and  an edgeedge with one O(3)NaFe3 trigonal pyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   5.976
_cell_length_c   13.014
_cell_angle_alpha   62.786
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   356.012
_cell_formula_units_Z   4
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  0.970  0.500  0.250  1.0
  Na  Na1  1  0.645  0.000  0.750  1.0
  Na  Na2  1  0.355  0.000  0.250  1.0
  Na  Na3  1  0.030  0.500  0.750  1.0
  Fe  Fe4  1  0.999  0.240  0.008  1.0
  Fe  Fe5  1  0.001  0.760  0.992  1.0
  Fe  Fe6  1  0.999  0.760  0.492  1.0
  Fe  Fe7  1  0.001  0.240  0.508  1.0
  Fe  Fe8  1  0.500  0.500  0.000  1.0
  Fe  Fe9  1  0.500  0.000  0.000  1.0
  Fe  Fe10  1  0.500  0.500  0.500  1.0
  Fe  Fe11  1  0.500  0.000  0.500  1.0
  O  O12  1  0.826  0.413  0.592  1.0
  O  O13  1  0.835  0.097  0.907  1.0
  O  O14  1  0.835  0.903  0.593  1.0
  O  O15  1  0.826  0.587  0.908  1.0
  O  O16  1  0.658  0.169  0.090  1.0
  O  O17  1  0.658  0.831  0.410  1.0
  O  O18  1  0.676  0.659  0.088  1.0
  O  O19  1  0.676  0.341  0.412  1.0
  O  O20  1  0.324  0.659  0.588  1.0
  O  O21  1  0.324  0.341  0.912  1.0
  O  O22  1  0.342  0.169  0.590  1.0
  O  O23  1  0.342  0.831  0.910  1.0
  O  O24  1  0.174  0.587  0.408  1.0
  O  O25  1  0.165  0.097  0.407  1.0
  O  O26  1  0.165  0.903  0.093  1.0
  O  O27  1  0.174  0.413  0.092  1.0
[/CIF]
.