The compound described by Ta2O5 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(5), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 0-35°. In the second Ta site, Ta(2) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms. In the third Ta site, Ta(3) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of distorted edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 13-32°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ta(3) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ta(3) and two equivalent Ta(2) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ta(1) and two equivalent Ta(3) atoms. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the eighth O site, O(8) is bonded in a linear geometry to two equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   18.241
_cell_length_b   18.241
_cell_length_c   3.831
_cell_angle_alpha   87.954
_cell_angle_beta   87.954
_cell_angle_gamma   12.492
_symmetry_Int_Tables_number   1
_cell_volume   275.550
_cell_formula_units_Z   3
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  0.949  0.949  0.903  1.0
  Ta  Ta1  1  0.051  0.051  0.097  1.0
  Ta  Ta2  1  0.295  0.295  0.472  1.0
  Ta  Ta3  1  0.705  0.705  0.528  1.0
  Ta  Ta4  1  0.128  0.128  0.580  1.0
  Ta  Ta5  1  0.872  0.872  0.420  1.0
  O  O6  1  0.551  0.551  0.133  1.0
  O  O7  1  0.449  0.449  0.867  1.0
  O  O8  1  0.695  0.695  0.034  1.0
  O  O9  1  0.305  0.305  0.966  1.0
  O  O10  1  0.068  0.068  0.602  1.0
  O  O11  1  0.932  0.932  0.398  1.0
  O  O12  1  0.181  0.181  0.545  1.0
  O  O13  1  0.819  0.819  0.455  1.0
  O  O14  1  0.113  0.113  0.085  1.0
  O  O15  1  0.887  0.887  0.915  1.0
  O  O16  1  0.634  0.634  0.577  1.0
  O  O17  1  0.366  0.366  0.423  1.0
  O  O18  1  0.000  0.000  0.000  1.0
  O  O19  1  0.500  0.000  0.500  1.0
  O  O20  1  0.000  0.500  0.500  1.0
[/CIF]
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The compound described by Ta2O5 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(5), one O(7), two equivalent O(1), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 0-35°. In the second Ta site, Ta(2) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms. In the third Ta site, Ta(3) is bonded to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms to form a mixture of distorted edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 13-32°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ta(3) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ta(3) and two equivalent Ta(2) atoms. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Ta(1) and two equivalent Ta(3) atoms. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the eighth O site, O(8) is bonded in a linear geometry to two equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   18.241
_cell_length_b   18.241
_cell_length_c   3.831
_cell_angle_alpha   87.954
_cell_angle_beta   87.954
_cell_angle_gamma   12.492
_symmetry_Int_Tables_number   1
_cell_volume   275.550
_cell_formula_units_Z   3
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  0.949  0.949  0.903  1.0
  Ta  Ta1  1  0.051  0.051  0.097  1.0
  Ta  Ta2  1  0.295  0.295  0.472  1.0
  Ta  Ta3  1  0.705  0.705  0.528  1.0
  Ta  Ta4  1  0.128  0.128  0.580  1.0
  Ta  Ta5  1  0.872  0.872  0.420  1.0
  O  O6  1  0.551  0.551  0.133  1.0
  O  O7  1  0.449  0.449  0.867  1.0
  O  O8  1  0.695  0.695  0.034  1.0
  O  O9  1  0.305  0.305  0.966  1.0
  O  O10  1  0.068  0.068  0.602  1.0
  O  O11  1  0.932  0.932  0.398  1.0
  O  O12  1  0.181  0.181  0.545  1.0
  O  O13  1  0.819  0.819  0.455  1.0
  O  O14  1  0.113  0.113  0.085  1.0
  O  O15  1  0.887  0.887  0.915  1.0
  O  O16  1  0.634  0.634  0.577  1.0
  O  O17  1  0.366  0.366  0.423  1.0
  O  O18  1  0.000  0.000  0.000  1.0
  O  O19  1  0.500  0.000  0.500  1.0
  O  O20  1  0.000  0.500  0.500  1.0
[/CIF]
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