The structure described by KNa2NiO2 crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one Ni(2), three equivalent Ni(1), one O(1), and one O(4) atom. In the second K site, K(2) is bonded in a 1-coordinate geometry to one O(3) atom. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to two equivalent O(2) and two equivalent O(4) atoms. In the third Na site, Na(3) is bonded in a distorted see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to three equivalent K(1), one O(2), and one O(4) atom. In the second Ni site, Ni(2) is bonded in a linear geometry to one K(1), one O(1), and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), two equivalent Na(1), two equivalent Na(3), and one Ni(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(2), two equivalent Na(1), two equivalent Na(3), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one K(1), two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. is represented by the CIF file [CIF]
data_KNa2NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.159
_cell_length_b   12.451
_cell_length_c   6.159
_cell_angle_alpha   90.290
_cell_angle_beta   118.754
_cell_angle_gamma   89.722
_symmetry_Int_Tables_number   1
_cell_volume   414.111
_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
  K  K0  1  0.188  0.631  0.813  1.0
  K  K1  1  0.313  0.128  0.686  1.0
  K  K2  1  0.686  0.872  0.313  1.0
  K  K3  1  0.813  0.369  0.187  1.0
  Na  Na4  1  0.228  0.000  0.228  1.0
  Na  Na5  1  0.270  0.500  0.270  1.0
  Na  Na6  1  0.730  0.500  0.730  1.0
  Na  Na7  1  0.772  0.000  0.772  1.0
  Na  Na8  1  0.224  0.749  0.278  1.0
  Na  Na9  1  0.776  0.251  0.721  1.0
  Na  Na10  1  0.722  0.749  0.776  1.0
  Na  Na11  1  0.279  0.251  0.224  1.0
  Ni  Ni12  1  0.752  0.624  0.248  1.0
  Ni  Ni13  1  0.248  0.376  0.752  1.0
  Ni  Ni14  1  0.252  0.876  0.748  1.0
  Ni  Ni15  1  0.748  0.124  0.252  1.0
  O  O16  1  0.082  0.863  0.918  1.0
  O  O17  1  0.583  0.636  0.417  1.0
  O  O18  1  0.418  0.364  0.582  1.0
  O  O19  1  0.917  0.137  0.083  1.0
  O  O20  1  0.421  0.886  0.579  1.0
  O  O21  1  0.579  0.114  0.421  1.0
  O  O22  1  0.079  0.385  0.921  1.0
  O  O23  1  0.921  0.615  0.079  1.0
[/CIF]
.
The structure described by KNa2NiO2 crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one Ni(2), three equivalent Ni(1), one O(1), and one O(4) atom. In the second K site, K(2) is bonded in a 1-coordinate geometry to one O(3) atom. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to two equivalent O(2) and two equivalent O(4) atoms. In the third Na site, Na(3) is bonded in a distorted see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to three equivalent K(1), one O(2), and one O(4) atom. In the second Ni site, Ni(2) is bonded in a linear geometry to one K(1), one O(1), and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), two equivalent Na(1), two equivalent Na(3), and one Ni(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(2), two equivalent Na(1), two equivalent Na(3), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one K(1), two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. is represented by the CIF file [CIF]
data_KNa2NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.159
_cell_length_b   12.451
_cell_length_c   6.159
_cell_angle_alpha   90.290
_cell_angle_beta   118.754
_cell_angle_gamma   89.722
_symmetry_Int_Tables_number   1
_cell_volume   414.111
_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
  K  K0  1  0.188  0.631  0.813  1.0
  K  K1  1  0.313  0.128  0.686  1.0
  K  K2  1  0.686  0.872  0.313  1.0
  K  K3  1  0.813  0.369  0.187  1.0
  Na  Na4  1  0.228  0.000  0.228  1.0
  Na  Na5  1  0.270  0.500  0.270  1.0
  Na  Na6  1  0.730  0.500  0.730  1.0
  Na  Na7  1  0.772  0.000  0.772  1.0
  Na  Na8  1  0.224  0.749  0.278  1.0
  Na  Na9  1  0.776  0.251  0.721  1.0
  Na  Na10  1  0.722  0.749  0.776  1.0
  Na  Na11  1  0.279  0.251  0.224  1.0
  Ni  Ni12  1  0.752  0.624  0.248  1.0
  Ni  Ni13  1  0.248  0.376  0.752  1.0
  Ni  Ni14  1  0.252  0.876  0.748  1.0
  Ni  Ni15  1  0.748  0.124  0.252  1.0
  O  O16  1  0.082  0.863  0.918  1.0
  O  O17  1  0.583  0.636  0.417  1.0
  O  O18  1  0.418  0.364  0.582  1.0
  O  O19  1  0.917  0.137  0.083  1.0
  O  O20  1  0.421  0.886  0.579  1.0
  O  O21  1  0.579  0.114  0.421  1.0
  O  O22  1  0.079  0.385  0.921  1.0
  O  O23  1  0.921  0.615  0.079  1.0
[/CIF]
.