The compound described by Na3NiO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a linear geometry to two equivalent O(1) atoms. Ni(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one Na(2), four equivalent Na(1), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing ONa5Ni octahedra. The corner-sharing octahedral tilt angles range from 3-21°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.476
_cell_length_b   9.476
_cell_length_c   4.612
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   414.090
_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  0.155  0.479  0.500  1.0
  Na  Na1  1  0.021  0.655  0.000  1.0
  Na  Na2  1  0.356  0.644  0.000  1.0
  Na  Na3  1  0.856  0.856  0.500  1.0
  Na  Na4  1  0.521  0.845  0.500  1.0
  Na  Na5  1  0.655  0.021  0.000  1.0
  Na  Na6  1  0.345  0.979  0.000  1.0
  Na  Na7  1  0.479  0.155  0.500  1.0
  Na  Na8  1  0.144  0.144  0.500  1.0
  Na  Na9  1  0.644  0.356  0.000  1.0
  Na  Na10  1  0.979  0.345  0.000  1.0
  Na  Na11  1  0.845  0.521  0.500  1.0
  Ni  Ni12  1  0.672  0.672  0.000  1.0
  Ni  Ni13  1  0.172  0.828  0.500  1.0
  Ni  Ni14  1  0.828  0.172  0.500  1.0
  Ni  Ni15  1  0.328  0.328  0.000  1.0
  O  O16  1  0.803  0.536  0.000  1.0
  O  O17  1  0.036  0.697  0.500  1.0
  O  O18  1  0.536  0.803  0.000  1.0
  O  O19  1  0.303  0.964  0.500  1.0
  O  O20  1  0.697  0.036  0.500  1.0
  O  O21  1  0.464  0.197  0.000  1.0
  O  O22  1  0.964  0.303  0.500  1.0
  O  O23  1  0.197  0.464  0.000  1.0
[/CIF]
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The compound described by Na3NiO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a linear geometry to two equivalent O(1) atoms. Ni(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one Na(2), four equivalent Na(1), and one Ni(1) atom to form a mixture of distorted corner and edge-sharing ONa5Ni octahedra. The corner-sharing octahedral tilt angles range from 3-21°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.476
_cell_length_b   9.476
_cell_length_c   4.612
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   414.090
_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  0.155  0.479  0.500  1.0
  Na  Na1  1  0.021  0.655  0.000  1.0
  Na  Na2  1  0.356  0.644  0.000  1.0
  Na  Na3  1  0.856  0.856  0.500  1.0
  Na  Na4  1  0.521  0.845  0.500  1.0
  Na  Na5  1  0.655  0.021  0.000  1.0
  Na  Na6  1  0.345  0.979  0.000  1.0
  Na  Na7  1  0.479  0.155  0.500  1.0
  Na  Na8  1  0.144  0.144  0.500  1.0
  Na  Na9  1  0.644  0.356  0.000  1.0
  Na  Na10  1  0.979  0.345  0.000  1.0
  Na  Na11  1  0.845  0.521  0.500  1.0
  Ni  Ni12  1  0.672  0.672  0.000  1.0
  Ni  Ni13  1  0.172  0.828  0.500  1.0
  Ni  Ni14  1  0.828  0.172  0.500  1.0
  Ni  Ni15  1  0.328  0.328  0.000  1.0
  O  O16  1  0.803  0.536  0.000  1.0
  O  O17  1  0.036  0.697  0.500  1.0
  O  O18  1  0.536  0.803  0.000  1.0
  O  O19  1  0.303  0.964  0.500  1.0
  O  O20  1  0.697  0.036  0.500  1.0
  O  O21  1  0.464  0.197  0.000  1.0
  O  O22  1  0.964  0.303  0.500  1.0
  O  O23  1  0.197  0.464  0.000  1.0
[/CIF]
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