The structure described by K3(NiO2)2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. In the second K site, K(2) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.497
_cell_length_b   5.497
_cell_length_c   10.708
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   112.291
_symmetry_Int_Tables_number   1
_cell_volume   299.337
_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
  K  K0  1  0.298  0.702  0.250  1.0
  K  K1  1  0.702  0.298  0.750  1.0
  K  K2  1  0.350  0.650  0.573  1.0
  K  K3  1  0.650  0.350  0.073  1.0
  K  K4  1  0.650  0.350  0.427  1.0
  K  K5  1  0.350  0.650  0.927  1.0
  Ni  Ni6  1  0.066  0.934  0.750  1.0
  Ni  Ni7  1  0.000  0.000  0.500  1.0
  Ni  Ni8  1  0.000  0.000  0.000  1.0
  Ni  Ni9  1  0.934  0.066  0.250  1.0
  O  O10  1  0.865  0.732  0.616  1.0
  O  O11  1  0.865  0.732  0.884  1.0
  O  O12  1  0.268  0.135  0.616  1.0
  O  O13  1  0.732  0.865  0.116  1.0
  O  O14  1  0.135  0.268  0.384  1.0
  O  O15  1  0.268  0.135  0.884  1.0
  O  O16  1  0.732  0.865  0.384  1.0
  O  O17  1  0.135  0.268  0.116  1.0
[/CIF]
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The structure described by K3(NiO2)2 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. In the second K site, K(2) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted square co-planar geometry to four equivalent O(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.497
_cell_length_b   5.497
_cell_length_c   10.708
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   112.291
_symmetry_Int_Tables_number   1
_cell_volume   299.337
_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
  K  K0  1  0.298  0.702  0.250  1.0
  K  K1  1  0.702  0.298  0.750  1.0
  K  K2  1  0.350  0.650  0.573  1.0
  K  K3  1  0.650  0.350  0.073  1.0
  K  K4  1  0.650  0.350  0.427  1.0
  K  K5  1  0.350  0.650  0.927  1.0
  Ni  Ni6  1  0.066  0.934  0.750  1.0
  Ni  Ni7  1  0.000  0.000  0.500  1.0
  Ni  Ni8  1  0.000  0.000  0.000  1.0
  Ni  Ni9  1  0.934  0.066  0.250  1.0
  O  O10  1  0.865  0.732  0.616  1.0
  O  O11  1  0.865  0.732  0.884  1.0
  O  O12  1  0.268  0.135  0.616  1.0
  O  O13  1  0.732  0.865  0.116  1.0
  O  O14  1  0.135  0.268  0.384  1.0
  O  O15  1  0.268  0.135  0.884  1.0
  O  O16  1  0.732  0.865  0.384  1.0
  O  O17  1  0.135  0.268  0.116  1.0
[/CIF]
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