The crystal structure described by NiO2 crystallizes in the orthorhombic Imma space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing NiO4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra and edges with two equivalent Ni(2)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Ni(1) and one Ni(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ni(1) and two equivalent Ni(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   5.547
_cell_length_c   5.547
_cell_angle_alpha   119.818
_cell_angle_beta   115.806
_cell_angle_gamma   93.867
_symmetry_Int_Tables_number   1
_cell_volume   124.173
_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
  Ni  Ni0  1  0.627  0.877  0.750  1.0
  Ni  Ni1  1  0.373  0.123  0.250  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.000  0.500  0.500  1.0
  O  O4  1  0.252  0.256  0.996  1.0
  O  O5  1  0.247  0.281  0.534  1.0
  O  O6  1  0.760  0.256  0.504  1.0
  O  O7  1  0.247  0.713  0.966  1.0
  O  O8  1  0.753  0.287  0.034  1.0
  O  O9  1  0.753  0.719  0.466  1.0
  O  O10  1  0.240  0.744  0.496  1.0
  O  O11  1  0.748  0.744  0.004  1.0
[/CIF]
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The crystal structure described by NiO2 crystallizes in the orthorhombic Imma space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing NiO4 tetrahedra. The corner-sharing octahedral tilt angles range from 57-58°. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O4 tetrahedra and edges with two equivalent Ni(2)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Ni(1) and one Ni(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ni(1) and two equivalent Ni(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   5.547
_cell_length_c   5.547
_cell_angle_alpha   119.818
_cell_angle_beta   115.806
_cell_angle_gamma   93.867
_symmetry_Int_Tables_number   1
_cell_volume   124.173
_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
  Ni  Ni0  1  0.627  0.877  0.750  1.0
  Ni  Ni1  1  0.373  0.123  0.250  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.000  0.500  0.500  1.0
  O  O4  1  0.252  0.256  0.996  1.0
  O  O5  1  0.247  0.281  0.534  1.0
  O  O6  1  0.760  0.256  0.504  1.0
  O  O7  1  0.247  0.713  0.966  1.0
  O  O8  1  0.753  0.287  0.034  1.0
  O  O9  1  0.753  0.719  0.466  1.0
  O  O10  1  0.240  0.744  0.496  1.0
  O  O11  1  0.748  0.744  0.004  1.0
[/CIF]
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