The compound described by Na(FeO2)2 crystallizes in the orthorhombic Pmm2 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the third Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the fourth Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2); one O(3); and four O(1,1) atoms to form edge-sharing FeO6 octahedra. In the second Fe site, Fe(1) is bonded to one O(2); one O(3); and four O(1,1) atoms to form edge-sharing FeO6 octahedra. In the third Fe site, Fe(2) is bonded to two O(1,1); two O(2,2); and two O(3,3) atoms to form edge-sharing FeO6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1); one Na(2); one Fe(2); and two Fe(1,1) atoms to form distorted ONa2Fe3 trigonal bipyramids that share corners with five O(1,1)Na2Fe3 trigonal bipyramids; corners with two equivalent O(3)NaFe3 trigonal pyramids; edges with four O(1,1)Na2Fe3 trigonal bipyramids; and edges with two O(3,3)NaFe3 trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), one Fe(1), and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded to one Na(1), one Fe(1), and two equivalent Fe(2) atoms to form ONaFe3 trigonal pyramids that share corners with four equivalent O(1)Na2Fe3 trigonal bipyramids; corners with three O(3,3)NaFe3 trigonal pyramids; and edges with four O(1,1)Na2Fe3 trigonal bipyramids. In the fourth O site, O(3) is bonded to one Na(1), one Fe(1), and two equivalent Fe(2) atoms to form ONaFe3 trigonal pyramids that share corners with four equivalent O(1)Na2Fe3 trigonal bipyramids; corners with three O(3,3)NaFe3 trigonal pyramids; and edges with four O(1,1)Na2Fe3 trigonal bipyramids. In the fifth O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), one Fe(1), and two equivalent Fe(2) atoms. In the sixth O site, O(1) is bonded to one Na(1); one Na(2); one Fe(2); and two Fe(1,1) atoms to form distorted ONa2Fe3 trigonal bipyramids that share corners with five O(1,1)Na2Fe3 trigonal bipyramids; corners with two equivalent O(3)NaFe3 trigonal pyramids; edges with four O(1,1)Na2Fe3 trigonal bipyramids; and edges with two O(3,3)NaFe3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.877
_cell_length_b   5.634
_cell_length_c   11.444
_cell_angle_alpha   90.007
_cell_angle_beta   89.985
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   314.391
_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  0.031  0.750  0.250  1.0
  Na  Na1  1  0.359  0.750  0.750  1.0
  Na  Na2  1  0.641  0.250  0.250  1.0
  Na  Na3  1  0.970  0.250  0.750  1.0
  Fe  Fe4  1  0.004  0.250  0.004  1.0
  Fe  Fe5  1  0.996  0.750  0.996  1.0
  Fe  Fe6  1  0.004  0.250  0.496  1.0
  Fe  Fe7  1  0.996  0.750  0.504  1.0
  Fe  Fe8  1  0.500  0.499  1.000  1.0
  Fe  Fe9  1  0.500  0.000  1.000  1.0
  Fe  Fe10  1  0.500  1.000  0.500  1.0
  Fe  Fe11  1  0.500  0.500  0.500  1.0
  O  O12  1  0.166  0.001  0.590  1.0
  O  O13  1  0.166  0.001  0.909  1.0
  O  O14  1  0.166  0.499  0.590  1.0
  O  O15  1  0.166  0.500  0.909  1.0
  O  O16  1  0.338  0.250  0.091  1.0
  O  O17  1  0.338  0.250  0.409  1.0
  O  O18  1  0.328  0.750  0.086  1.0
  O  O19  1  0.329  0.750  0.414  1.0
  O  O20  1  0.672  0.250  0.587  1.0
  O  O21  1  0.672  0.250  0.914  1.0
  O  O22  1  0.662  0.750  0.590  1.0
  O  O23  1  0.662  0.750  0.910  1.0
  O  O24  1  0.834  0.999  0.410  1.0
  O  O25  1  0.834  0.501  0.409  1.0
  O  O26  1  0.834  0.998  0.091  1.0
  O  O27  1  0.834  0.502  0.091  1.0
[/CIF]
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The compound described by Na(FeO2)2 crystallizes in the orthorhombic Pmm2 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the third Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. In the fourth Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2); one O(3); and four O(1,1) atoms to form edge-sharing FeO6 octahedra. In the second Fe site, Fe(1) is bonded to one O(2); one O(3); and four O(1,1) atoms to form edge-sharing FeO6 octahedra. In the third Fe site, Fe(2) is bonded to two O(1,1); two O(2,2); and two O(3,3) atoms to form edge-sharing FeO6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1); one Na(2); one Fe(2); and two Fe(1,1) atoms to form distorted ONa2Fe3 trigonal bipyramids that share corners with five O(1,1)Na2Fe3 trigonal bipyramids; corners with two equivalent O(3)NaFe3 trigonal pyramids; edges with four O(1,1)Na2Fe3 trigonal bipyramids; and edges with two O(3,3)NaFe3 trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), one Fe(1), and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded to one Na(1), one Fe(1), and two equivalent Fe(2) atoms to form ONaFe3 trigonal pyramids that share corners with four equivalent O(1)Na2Fe3 trigonal bipyramids; corners with three O(3,3)NaFe3 trigonal pyramids; and edges with four O(1,1)Na2Fe3 trigonal bipyramids. In the fourth O site, O(3) is bonded to one Na(1), one Fe(1), and two equivalent Fe(2) atoms to form ONaFe3 trigonal pyramids that share corners with four equivalent O(1)Na2Fe3 trigonal bipyramids; corners with three O(3,3)NaFe3 trigonal pyramids; and edges with four O(1,1)Na2Fe3 trigonal bipyramids. In the fifth O site, O(2) is bonded in a rectangular see-saw-like geometry to one Na(2), one Fe(1), and two equivalent Fe(2) atoms. In the sixth O site, O(1) is bonded to one Na(1); one Na(2); one Fe(2); and two Fe(1,1) atoms to form distorted ONa2Fe3 trigonal bipyramids that share corners with five O(1,1)Na2Fe3 trigonal bipyramids; corners with two equivalent O(3)NaFe3 trigonal pyramids; edges with four O(1,1)Na2Fe3 trigonal bipyramids; and edges with two O(3,3)NaFe3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.877
_cell_length_b   5.634
_cell_length_c   11.444
_cell_angle_alpha   90.007
_cell_angle_beta   89.985
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   314.391
_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  0.031  0.750  0.250  1.0
  Na  Na1  1  0.359  0.750  0.750  1.0
  Na  Na2  1  0.641  0.250  0.250  1.0
  Na  Na3  1  0.970  0.250  0.750  1.0
  Fe  Fe4  1  0.004  0.250  0.004  1.0
  Fe  Fe5  1  0.996  0.750  0.996  1.0
  Fe  Fe6  1  0.004  0.250  0.496  1.0
  Fe  Fe7  1  0.996  0.750  0.504  1.0
  Fe  Fe8  1  0.500  0.499  1.000  1.0
  Fe  Fe9  1  0.500  0.000  1.000  1.0
  Fe  Fe10  1  0.500  1.000  0.500  1.0
  Fe  Fe11  1  0.500  0.500  0.500  1.0
  O  O12  1  0.166  0.001  0.590  1.0
  O  O13  1  0.166  0.001  0.909  1.0
  O  O14  1  0.166  0.499  0.590  1.0
  O  O15  1  0.166  0.500  0.909  1.0
  O  O16  1  0.338  0.250  0.091  1.0
  O  O17  1  0.338  0.250  0.409  1.0
  O  O18  1  0.328  0.750  0.086  1.0
  O  O19  1  0.329  0.750  0.414  1.0
  O  O20  1  0.672  0.250  0.587  1.0
  O  O21  1  0.672  0.250  0.914  1.0
  O  O22  1  0.662  0.750  0.590  1.0
  O  O23  1  0.662  0.750  0.910  1.0
  O  O24  1  0.834  0.999  0.410  1.0
  O  O25  1  0.834  0.501  0.409  1.0
  O  O26  1  0.834  0.998  0.091  1.0
  O  O27  1  0.834  0.502  0.091  1.0
[/CIF]
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