The compound described by Na3NiO2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(2) and two equivalent O(1) atoms. In the third Na site, Na(3) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. Ni(1) is bonded in a linear geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.542
_cell_length_b   5.919
_cell_length_c   7.990
_cell_angle_alpha   67.170
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   372.287
_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  0.786  0.736  0.689  1.0
  Na  Na1  1  0.532  0.240  0.125  1.0
  Na  Na2  1  0.965  0.252  1.000  1.0
  Na  Na3  1  0.286  0.265  0.811  1.0
  Na  Na4  1  0.968  0.240  0.625  1.0
  Na  Na5  1  0.535  0.252  0.500  1.0
  Na  Na6  1  0.465  0.748  0.500  1.0
  Na  Na7  1  0.032  0.760  0.375  1.0
  Na  Na8  1  0.714  0.736  0.189  1.0
  Na  Na9  1  0.035  0.748  0.000  1.0
  Na  Na10  1  0.468  0.760  0.875  1.0
  Na  Na11  1  0.214  0.265  0.311  1.0
  Ni  Ni12  1  0.173  0.795  0.672  1.0
  Ni  Ni13  1  0.673  0.205  0.828  1.0
  Ni  Ni14  1  0.327  0.795  0.172  1.0
  Ni  Ni15  1  0.827  0.205  0.328  1.0
  O  O16  1  0.040  0.544  0.722  1.0
  O  O17  1  0.540  0.456  0.778  1.0
  O  O18  1  0.687  0.963  0.382  1.0
  O  O19  1  0.187  0.037  0.118  1.0
  O  O20  1  0.813  0.963  0.882  1.0
  O  O21  1  0.313  0.037  0.618  1.0
  O  O22  1  0.460  0.544  0.222  1.0
  O  O23  1  0.960  0.456  0.278  1.0
[/CIF]
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The compound described by Na3NiO2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(2) and two equivalent O(1) atoms. In the third Na site, Na(3) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. Ni(1) is bonded in a linear geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.542
_cell_length_b   5.919
_cell_length_c   7.990
_cell_angle_alpha   67.170
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   372.287
_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  0.786  0.736  0.689  1.0
  Na  Na1  1  0.532  0.240  0.125  1.0
  Na  Na2  1  0.965  0.252  1.000  1.0
  Na  Na3  1  0.286  0.265  0.811  1.0
  Na  Na4  1  0.968  0.240  0.625  1.0
  Na  Na5  1  0.535  0.252  0.500  1.0
  Na  Na6  1  0.465  0.748  0.500  1.0
  Na  Na7  1  0.032  0.760  0.375  1.0
  Na  Na8  1  0.714  0.736  0.189  1.0
  Na  Na9  1  0.035  0.748  0.000  1.0
  Na  Na10  1  0.468  0.760  0.875  1.0
  Na  Na11  1  0.214  0.265  0.311  1.0
  Ni  Ni12  1  0.173  0.795  0.672  1.0
  Ni  Ni13  1  0.673  0.205  0.828  1.0
  Ni  Ni14  1  0.327  0.795  0.172  1.0
  Ni  Ni15  1  0.827  0.205  0.328  1.0
  O  O16  1  0.040  0.544  0.722  1.0
  O  O17  1  0.540  0.456  0.778  1.0
  O  O18  1  0.687  0.963  0.382  1.0
  O  O19  1  0.187  0.037  0.118  1.0
  O  O20  1  0.813  0.963  0.882  1.0
  O  O21  1  0.313  0.037  0.618  1.0
  O  O22  1  0.460  0.544  0.222  1.0
  O  O23  1  0.960  0.456  0.278  1.0
[/CIF]
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