The material described by Na3(NiO2)2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded to one Na(2), three equivalent Na(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-75°. is represented by the CIF file [CIF]
data_Na3(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.886
_cell_length_b   4.886
_cell_length_c   10.483
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.350
_symmetry_Int_Tables_number   1
_cell_volume   236.107
_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  0.649  0.351  0.065  1.0
  Na  Na1  1  0.649  0.351  0.435  1.0
  Na  Na2  1  0.351  0.649  0.565  1.0
  Na  Na3  1  0.314  0.686  0.250  1.0
  Na  Na4  1  0.686  0.314  0.750  1.0
  Na  Na5  1  0.351  0.649  0.935  1.0
  Ni  Ni6  1  0.000  0.000  0.000  1.0
  Ni  Ni7  1  0.928  0.072  0.250  1.0
  Ni  Ni8  1  0.000  0.000  0.500  1.0
  Ni  Ni9  1  0.072  0.928  0.750  1.0
  O  O10  1  0.140  0.296  0.119  1.0
  O  O11  1  0.140  0.296  0.381  1.0
  O  O12  1  0.296  0.140  0.881  1.0
  O  O13  1  0.296  0.140  0.619  1.0
  O  O14  1  0.704  0.860  0.381  1.0
  O  O15  1  0.704  0.860  0.119  1.0
  O  O16  1  0.860  0.704  0.619  1.0
  O  O17  1  0.860  0.704  0.881  1.0
[/CIF]
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The material described by Na3(NiO2)2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded to one Na(2), three equivalent Na(1), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-75°. is represented by the CIF file [CIF]
data_Na3(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.886
_cell_length_b   4.886
_cell_length_c   10.483
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.350
_symmetry_Int_Tables_number   1
_cell_volume   236.107
_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  0.649  0.351  0.065  1.0
  Na  Na1  1  0.649  0.351  0.435  1.0
  Na  Na2  1  0.351  0.649  0.565  1.0
  Na  Na3  1  0.314  0.686  0.250  1.0
  Na  Na4  1  0.686  0.314  0.750  1.0
  Na  Na5  1  0.351  0.649  0.935  1.0
  Ni  Ni6  1  0.000  0.000  0.000  1.0
  Ni  Ni7  1  0.928  0.072  0.250  1.0
  Ni  Ni8  1  0.000  0.000  0.500  1.0
  Ni  Ni9  1  0.072  0.928  0.750  1.0
  O  O10  1  0.140  0.296  0.119  1.0
  O  O11  1  0.140  0.296  0.381  1.0
  O  O12  1  0.296  0.140  0.881  1.0
  O  O13  1  0.296  0.140  0.619  1.0
  O  O14  1  0.704  0.860  0.381  1.0
  O  O15  1  0.704  0.860  0.119  1.0
  O  O16  1  0.860  0.704  0.619  1.0
  O  O17  1  0.860  0.704  0.881  1.0
[/CIF]
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