The structure described by Ta2O3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form a mixture of face, corner, and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 42-46°. In the second Ta site, Ta(2) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of face, corner, and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 42-46°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ta(1) and three equivalent Ta(2) atoms. In the second O site, O(2) is bonded in a distorted pentagonal planar geometry to two equivalent Ta(2) and three equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.127
_cell_length_b   6.127
_cell_length_c   7.596
_cell_angle_alpha   66.853
_cell_angle_beta   66.853
_cell_angle_gamma   26.780
_symmetry_Int_Tables_number   1
_cell_volume   117.531
_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
  Ta  Ta0  1  0.164  0.164  0.155  1.0
  Ta  Ta1  1  0.836  0.836  0.845  1.0
  Ta  Ta2  1  0.340  0.340  0.357  1.0
  Ta  Ta3  1  0.660  0.660  0.643  1.0
  O  O4  1  0.138  0.138  0.445  1.0
  O  O5  1  0.862  0.862  0.555  1.0
  O  O6  1  0.187  0.187  0.846  1.0
  O  O7  1  0.813  0.813  0.154  1.0
  O  O8  1  0.473  0.473  0.792  1.0
  O  O9  1  0.527  0.527  0.208  1.0
[/CIF]
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The structure described by Ta2O3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(2) atoms to form a mixture of face, corner, and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 42-46°. In the second Ta site, Ta(2) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of face, corner, and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 42-46°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ta(1) and three equivalent Ta(2) atoms. In the second O site, O(2) is bonded in a distorted pentagonal planar geometry to two equivalent Ta(2) and three equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.127
_cell_length_b   6.127
_cell_length_c   7.596
_cell_angle_alpha   66.853
_cell_angle_beta   66.853
_cell_angle_gamma   26.780
_symmetry_Int_Tables_number   1
_cell_volume   117.531
_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
  Ta  Ta0  1  0.164  0.164  0.155  1.0
  Ta  Ta1  1  0.836  0.836  0.845  1.0
  Ta  Ta2  1  0.340  0.340  0.357  1.0
  Ta  Ta3  1  0.660  0.660  0.643  1.0
  O  O4  1  0.138  0.138  0.445  1.0
  O  O5  1  0.862  0.862  0.555  1.0
  O  O6  1  0.187  0.187  0.846  1.0
  O  O7  1  0.813  0.813  0.154  1.0
  O  O8  1  0.473  0.473  0.792  1.0
  O  O9  1  0.527  0.527  0.208  1.0
[/CIF]
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