The crystal structure described by NbO2 is beta Vanadium nitride-like structured and crystallizes in the tetragonal I4_1/a space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the second Nb site, Nb(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 33-57°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1) and two equivalent Nb(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(2) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(2) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.040
_cell_length_b   10.249
_cell_length_c   10.248
_cell_angle_alpha   85.019
_cell_angle_beta   72.860
_cell_angle_gamma   72.865
_symmetry_Int_Tables_number   1
_cell_volume   579.295
_cell_formula_units_Z   16
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
  Nb  Nb0  1  0.140  0.511  0.262  1.0
  Nb  Nb1  1  0.402  0.238  0.511  1.0
  Nb  Nb2  1  0.151  0.262  0.989  1.0
  Nb  Nb3  1  0.912  0.989  0.238  1.0
  Nb  Nb4  1  0.860  0.489  0.738  1.0
  Nb  Nb5  1  0.598  0.762  0.489  1.0
  Nb  Nb6  1  0.849  0.738  0.011  1.0
  Nb  Nb7  1  0.088  0.011  0.762  1.0
  Nb  Nb8  1  0.605  0.490  0.240  1.0
  Nb  Nb9  1  0.846  0.260  0.490  1.0
  Nb  Nb10  1  0.596  0.240  0.010  1.0
  Nb  Nb11  1  0.336  0.010  0.260  1.0
  Nb  Nb12  1  0.395  0.510  0.760  1.0
  Nb  Nb13  1  0.154  0.740  0.510  1.0
  Nb  Nb14  1  0.404  0.760  0.990  1.0
  Nb  Nb15  1  0.664  0.990  0.740  1.0
  O  O16  1  0.775  0.350  0.100  1.0
  O  O17  1  0.876  0.399  0.350  1.0
  O  O18  1  0.626  0.100  0.149  1.0
  O  O19  1  0.226  0.150  0.399  1.0
  O  O20  1  0.225  0.650  0.900  1.0
  O  O21  1  0.124  0.601  0.650  1.0
  O  O22  1  0.374  0.900  0.851  1.0
  O  O23  1  0.774  0.850  0.601  1.0
  O  O24  1  0.257  0.362  0.112  1.0
  O  O25  1  0.368  0.388  0.362  1.0
  O  O26  1  0.118  0.112  0.138  1.0
  O  O27  1  0.730  0.138  0.388  1.0
  O  O28  1  0.743  0.638  0.888  1.0
  O  O29  1  0.632  0.612  0.638  1.0
  O  O30  1  0.882  0.888  0.862  1.0
  O  O31  1  0.270  0.862  0.612  1.0
  O  O32  1  0.977  0.151  0.902  1.0
  O  O33  1  0.879  0.598  0.150  1.0
  O  O34  1  0.627  0.902  0.350  1.0
  O  O35  1  0.029  0.349  0.598  1.0
  O  O36  1  0.023  0.849  0.098  1.0
  O  O37  1  0.121  0.402  0.850  1.0
  O  O38  1  0.373  0.098  0.650  1.0
  O  O39  1  0.971  0.651  0.402  1.0
  O  O40  1  0.478  0.139  0.887  1.0
  O  O41  1  0.365  0.613  0.139  1.0
  O  O42  1  0.116  0.887  0.361  1.0
  O  O43  1  0.503  0.361  0.613  1.0
  O  O44  1  0.522  0.861  0.113  1.0
  O  O45  1  0.635  0.387  0.861  1.0
  O  O46  1  0.884  0.113  0.639  1.0
  O  O47  1  0.497  0.639  0.387  1.0
[/CIF]
.
The crystal structure described by NbO2 is beta Vanadium nitride-like structured and crystallizes in the tetragonal I4_1/a space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the second Nb site, Nb(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 33-57°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1) and two equivalent Nb(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Nb(2) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(2) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Nb(1) and two equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NbO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.040
_cell_length_b   10.249
_cell_length_c   10.248
_cell_angle_alpha   85.019
_cell_angle_beta   72.860
_cell_angle_gamma   72.865
_symmetry_Int_Tables_number   1
_cell_volume   579.295
_cell_formula_units_Z   16
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
  Nb  Nb0  1  0.140  0.511  0.262  1.0
  Nb  Nb1  1  0.402  0.238  0.511  1.0
  Nb  Nb2  1  0.151  0.262  0.989  1.0
  Nb  Nb3  1  0.912  0.989  0.238  1.0
  Nb  Nb4  1  0.860  0.489  0.738  1.0
  Nb  Nb5  1  0.598  0.762  0.489  1.0
  Nb  Nb6  1  0.849  0.738  0.011  1.0
  Nb  Nb7  1  0.088  0.011  0.762  1.0
  Nb  Nb8  1  0.605  0.490  0.240  1.0
  Nb  Nb9  1  0.846  0.260  0.490  1.0
  Nb  Nb10  1  0.596  0.240  0.010  1.0
  Nb  Nb11  1  0.336  0.010  0.260  1.0
  Nb  Nb12  1  0.395  0.510  0.760  1.0
  Nb  Nb13  1  0.154  0.740  0.510  1.0
  Nb  Nb14  1  0.404  0.760  0.990  1.0
  Nb  Nb15  1  0.664  0.990  0.740  1.0
  O  O16  1  0.775  0.350  0.100  1.0
  O  O17  1  0.876  0.399  0.350  1.0
  O  O18  1  0.626  0.100  0.149  1.0
  O  O19  1  0.226  0.150  0.399  1.0
  O  O20  1  0.225  0.650  0.900  1.0
  O  O21  1  0.124  0.601  0.650  1.0
  O  O22  1  0.374  0.900  0.851  1.0
  O  O23  1  0.774  0.850  0.601  1.0
  O  O24  1  0.257  0.362  0.112  1.0
  O  O25  1  0.368  0.388  0.362  1.0
  O  O26  1  0.118  0.112  0.138  1.0
  O  O27  1  0.730  0.138  0.388  1.0
  O  O28  1  0.743  0.638  0.888  1.0
  O  O29  1  0.632  0.612  0.638  1.0
  O  O30  1  0.882  0.888  0.862  1.0
  O  O31  1  0.270  0.862  0.612  1.0
  O  O32  1  0.977  0.151  0.902  1.0
  O  O33  1  0.879  0.598  0.150  1.0
  O  O34  1  0.627  0.902  0.350  1.0
  O  O35  1  0.029  0.349  0.598  1.0
  O  O36  1  0.023  0.849  0.098  1.0
  O  O37  1  0.121  0.402  0.850  1.0
  O  O38  1  0.373  0.098  0.650  1.0
  O  O39  1  0.971  0.651  0.402  1.0
  O  O40  1  0.478  0.139  0.887  1.0
  O  O41  1  0.365  0.613  0.139  1.0
  O  O42  1  0.116  0.887  0.361  1.0
  O  O43  1  0.503  0.361  0.613  1.0
  O  O44  1  0.522  0.861  0.113  1.0
  O  O45  1  0.635  0.387  0.861  1.0
  O  O46  1  0.884  0.113  0.639  1.0
  O  O47  1  0.497  0.639  0.387  1.0
[/CIF]
.