The structure described by Na2NiO2 crystallizes in the tetragonal I4/mmm space group. Na(1) is bonded to four equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing NaO4 trigonal pyramids. Ni(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded in a 5-coordinate geometry to four equivalent Na(1) and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na2NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.375
_cell_length_b   4.375
_cell_length_c   6.023
_cell_angle_alpha   111.280
_cell_angle_beta   111.280
_cell_angle_gamma   90.010
_symmetry_Int_Tables_number   1
_cell_volume   98.951
_cell_formula_units_Z   1
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  0.750  0.250  0.500  1.0
  Na  Na1  1  0.250  0.750  0.500  1.0
  Ni  Ni2  1  0.500  0.500  1.000  1.0
  O  O3  1  0.333  0.333  0.666  1.0
  O  O4  1  0.667  0.667  0.334  1.0
[/CIF]
.
The structure described by Na2NiO2 crystallizes in the tetragonal I4/mmm space group. Na(1) is bonded to four equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing NaO4 trigonal pyramids. Ni(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded in a 5-coordinate geometry to four equivalent Na(1) and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na2NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.375
_cell_length_b   4.375
_cell_length_c   6.023
_cell_angle_alpha   111.280
_cell_angle_beta   111.280
_cell_angle_gamma   90.010
_symmetry_Int_Tables_number   1
_cell_volume   98.951
_cell_formula_units_Z   1
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  0.750  0.250  0.500  1.0
  Na  Na1  1  0.250  0.750  0.500  1.0
  Ni  Ni2  1  0.500  0.500  1.000  1.0
  O  O3  1  0.333  0.333  0.666  1.0
  O  O4  1  0.667  0.667  0.334  1.0
[/CIF]
.