The crystal structure described by Na2NiO3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-15°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-12°. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. is represented by the CIF card [CIF]
data_Na2NiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.241
_cell_length_b   5.241
_cell_length_c   5.621
_cell_angle_alpha   80.776
_cell_angle_beta   99.224
_cell_angle_gamma   59.995
_symmetry_Int_Tables_number   1
_cell_volume   126.662
_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  0.157  0.157  0.500  1.0
  Na  Na1  1  0.843  0.843  0.500  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Ni  Ni4  1  0.667  0.667  0.000  1.0
  Ni  Ni5  1  0.333  0.333  0.000  1.0
  O  O6  1  0.308  0.692  0.801  1.0
  O  O7  1  0.067  0.555  0.198  1.0
  O  O8  1  0.445  0.933  0.198  1.0
  O  O9  1  0.933  0.445  0.802  1.0
  O  O10  1  0.555  0.067  0.802  1.0
  O  O11  1  0.692  0.308  0.199  1.0
[/CIF]
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The crystal structure described by Na2NiO3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Ni(1)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-18°. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 18°. Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-15°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ni(1) atoms to form a mixture of corner and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-12°. In the second O site, O(2) is bonded to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. is represented by the CIF card [CIF]
data_Na2NiO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.241
_cell_length_b   5.241
_cell_length_c   5.621
_cell_angle_alpha   80.776
_cell_angle_beta   99.224
_cell_angle_gamma   59.995
_symmetry_Int_Tables_number   1
_cell_volume   126.662
_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  0.157  0.157  0.500  1.0
  Na  Na1  1  0.843  0.843  0.500  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Ni  Ni4  1  0.667  0.667  0.000  1.0
  Ni  Ni5  1  0.333  0.333  0.000  1.0
  O  O6  1  0.308  0.692  0.801  1.0
  O  O7  1  0.067  0.555  0.198  1.0
  O  O8  1  0.445  0.933  0.198  1.0
  O  O9  1  0.933  0.445  0.802  1.0
  O  O10  1  0.555  0.067  0.802  1.0
  O  O11  1  0.692  0.308  0.199  1.0
[/CIF]
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