The compound described by TaO2 is beta Vanadium nitride-like structured and crystallizes in the tetragonal I4_1/a space group. There are two inequivalent Ta sites. In the first Ta site, Ta(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 corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 32-57°. In the second Ta site, Ta(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 corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 32-57°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ta(1) and two equivalent Ta(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ta(2) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ta(2) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(1) and two equivalent Ta(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.228
_cell_length_b   10.228
_cell_length_c   10.228
_cell_angle_alpha   94.975
_cell_angle_beta   94.975
_cell_angle_gamma   145.747
_symmetry_Int_Tables_number   1
_cell_volume   575.454
_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
  Ta  Ta0  1  0.783  0.276  0.757  1.0
  Ta  Ta1  1  0.526  0.269  0.992  1.0
  Ta  Ta2  1  0.276  0.533  0.008  1.0
  Ta  Ta3  1  0.519  0.026  0.243  1.0
  Ta  Ta4  1  0.467  0.474  0.743  1.0
  Ta  Ta5  1  0.724  0.481  0.508  1.0
  Ta  Ta6  1  0.974  0.217  0.492  1.0
  Ta  Ta7  1  0.731  0.724  0.257  1.0
  Ta  Ta8  1  0.214  0.726  0.741  1.0
  Ta  Ta9  1  0.976  0.735  0.012  1.0
  Ta  Ta10  1  0.723  0.964  0.988  1.0
  Ta  Ta11  1  0.985  0.473  0.259  1.0
  Ta  Ta12  1  0.036  0.024  0.759  1.0
  Ta  Ta13  1  0.274  0.015  0.488  1.0
  Ta  Ta14  1  0.527  0.786  0.512  1.0
  Ta  Ta15  1  0.265  0.277  0.241  1.0
  O  O16  1  0.394  0.757  0.888  1.0
  O  O17  1  0.007  0.619  0.863  1.0
  O  O18  1  0.756  0.144  0.137  1.0
  O  O19  1  0.869  0.506  0.112  1.0
  O  O20  1  0.856  0.993  0.612  1.0
  O  O21  1  0.243  0.131  0.637  1.0
  O  O22  1  0.494  0.606  0.363  1.0
  O  O23  1  0.381  0.244  0.388  1.0
  O  O24  1  0.899  0.249  0.899  1.0
  O  O25  1  0.499  0.100  0.850  1.0
  O  O26  1  0.249  0.649  0.150  1.0
  O  O27  1  0.350  0.999  0.101  1.0
  O  O28  1  0.351  0.501  0.601  1.0
  O  O29  1  0.751  0.650  0.650  1.0
  O  O30  1  0.001  0.101  0.350  1.0
  O  O31  1  0.900  0.751  0.399  1.0
  O  O32  1  0.628  0.764  0.111  1.0
  O  O33  1  0.014  0.403  0.636  1.0
  O  O34  1  0.767  0.378  0.364  1.0
  O  O35  1  0.653  0.517  0.889  1.0
  O  O36  1  0.622  0.986  0.389  1.0
  O  O37  1  0.236  0.347  0.864  1.0
  O  O38  1  0.483  0.372  0.136  1.0
  O  O39  1  0.597  0.233  0.611  1.0
  O  O40  1  0.092  0.246  0.099  1.0
  O  O41  1  0.496  0.896  0.654  1.0
  O  O42  1  0.243  0.842  0.346  1.0
  O  O43  1  0.146  0.993  0.901  1.0
  O  O44  1  0.158  0.504  0.401  1.0
  O  O45  1  0.754  0.854  0.846  1.0
  O  O46  1  0.007  0.908  0.154  1.0
  O  O47  1  0.104  0.757  0.599  1.0
[/CIF]
.
The compound described by TaO2 is beta Vanadium nitride-like structured and crystallizes in the tetragonal I4_1/a space group. There are two inequivalent Ta sites. In the first Ta site, Ta(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 corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 32-57°. In the second Ta site, Ta(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 corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 32-57°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ta(1) and two equivalent Ta(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ta(2) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ta(2) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(1) and two equivalent Ta(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.228
_cell_length_b   10.228
_cell_length_c   10.228
_cell_angle_alpha   94.975
_cell_angle_beta   94.975
_cell_angle_gamma   145.747
_symmetry_Int_Tables_number   1
_cell_volume   575.454
_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
  Ta  Ta0  1  0.783  0.276  0.757  1.0
  Ta  Ta1  1  0.526  0.269  0.992  1.0
  Ta  Ta2  1  0.276  0.533  0.008  1.0
  Ta  Ta3  1  0.519  0.026  0.243  1.0
  Ta  Ta4  1  0.467  0.474  0.743  1.0
  Ta  Ta5  1  0.724  0.481  0.508  1.0
  Ta  Ta6  1  0.974  0.217  0.492  1.0
  Ta  Ta7  1  0.731  0.724  0.257  1.0
  Ta  Ta8  1  0.214  0.726  0.741  1.0
  Ta  Ta9  1  0.976  0.735  0.012  1.0
  Ta  Ta10  1  0.723  0.964  0.988  1.0
  Ta  Ta11  1  0.985  0.473  0.259  1.0
  Ta  Ta12  1  0.036  0.024  0.759  1.0
  Ta  Ta13  1  0.274  0.015  0.488  1.0
  Ta  Ta14  1  0.527  0.786  0.512  1.0
  Ta  Ta15  1  0.265  0.277  0.241  1.0
  O  O16  1  0.394  0.757  0.888  1.0
  O  O17  1  0.007  0.619  0.863  1.0
  O  O18  1  0.756  0.144  0.137  1.0
  O  O19  1  0.869  0.506  0.112  1.0
  O  O20  1  0.856  0.993  0.612  1.0
  O  O21  1  0.243  0.131  0.637  1.0
  O  O22  1  0.494  0.606  0.363  1.0
  O  O23  1  0.381  0.244  0.388  1.0
  O  O24  1  0.899  0.249  0.899  1.0
  O  O25  1  0.499  0.100  0.850  1.0
  O  O26  1  0.249  0.649  0.150  1.0
  O  O27  1  0.350  0.999  0.101  1.0
  O  O28  1  0.351  0.501  0.601  1.0
  O  O29  1  0.751  0.650  0.650  1.0
  O  O30  1  0.001  0.101  0.350  1.0
  O  O31  1  0.900  0.751  0.399  1.0
  O  O32  1  0.628  0.764  0.111  1.0
  O  O33  1  0.014  0.403  0.636  1.0
  O  O34  1  0.767  0.378  0.364  1.0
  O  O35  1  0.653  0.517  0.889  1.0
  O  O36  1  0.622  0.986  0.389  1.0
  O  O37  1  0.236  0.347  0.864  1.0
  O  O38  1  0.483  0.372  0.136  1.0
  O  O39  1  0.597  0.233  0.611  1.0
  O  O40  1  0.092  0.246  0.099  1.0
  O  O41  1  0.496  0.896  0.654  1.0
  O  O42  1  0.243  0.842  0.346  1.0
  O  O43  1  0.146  0.993  0.901  1.0
  O  O44  1  0.158  0.504  0.401  1.0
  O  O45  1  0.754  0.854  0.846  1.0
  O  O46  1  0.007  0.908  0.154  1.0
  O  O47  1  0.104  0.757  0.599  1.0
[/CIF]
.