The material structure described by Ta9V2O25 crystallizes in the tetragonal I4/m space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(5) and four O(6,6) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 1-27°. In the third Ta site, Ta(3) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(1) atoms to form distorted TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent V(1)O4 tetrahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-27°. V(1) is bonded to four equivalent O(4) atoms to form distorted VO4 tetrahedra that share corners with four equivalent Ta(3)O6 octahedra and edges with two equivalent V(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Ta(3) and two equivalent V(1) atoms. In the second O site, O(5) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the third O site, O(6) is bonded in a linear geometry to one Ta(1) and one Ta(2) atom. In the fourth O site, O(6) is bonded in a linear geometry to one Ta(1) and one Ta(2) atom. In the fifth O site, O(7) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. In the sixth O site, O(1) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(3) atoms. In the seventh O site, O(2) is bonded in a distorted T-shaped geometry to one Ta(3) and two equivalent Ta(2) atoms. In the eighth O site, O(3) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. is represented by the CIF file [CIF]
data_Ta9V2O25
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.436
_cell_length_b   11.436
_cell_length_c   11.436
_cell_angle_alpha   91.740
_cell_angle_beta   91.740
_cell_angle_gamma   159.929
_symmetry_Int_Tables_number   1
_cell_volume   505.475
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.222  0.901  0.124  1.0
  Ta  Ta2  1  0.778  0.099  0.876  1.0
  Ta  Ta3  1  0.901  0.778  0.679  1.0
  Ta  Ta4  1  0.099  0.222  0.321  1.0
  Ta  Ta5  1  0.125  0.680  0.805  1.0
  Ta  Ta6  1  0.875  0.320  0.195  1.0
  Ta  Ta7  1  0.680  0.875  0.555  1.0
  Ta  Ta8  1  0.320  0.125  0.445  1.0
  V  V9  1  0.750  0.250  0.500  1.0
  V  V10  1  0.250  0.750  0.500  1.0
  O  O11  1  0.350  0.838  0.188  1.0
  O  O12  1  0.650  0.162  0.812  1.0
  O  O13  1  0.838  0.650  0.488  1.0
  O  O14  1  0.162  0.350  0.512  1.0
  O  O15  1  0.251  0.612  0.863  1.0
  O  O16  1  0.749  0.388  0.137  1.0
  O  O17  1  0.612  0.749  0.361  1.0
  O  O18  1  0.388  0.251  0.639  1.0
  O  O19  1  0.178  0.787  0.966  1.0
  O  O20  1  0.822  0.213  0.034  1.0
  O  O21  1  0.787  0.822  0.609  1.0
  O  O22  1  0.213  0.178  0.391  1.0
  O  O23  1  0.084  0.560  0.644  1.0
  O  O24  1  0.916  0.440  0.356  1.0
  O  O25  1  0.560  0.916  0.476  1.0
  O  O26  1  0.440  0.084  0.524  1.0
  O  O27  1  0.500  0.500  0.000  1.0
  O  O28  1  0.117  0.950  0.066  1.0
  O  O29  1  0.883  0.050  0.934  1.0
  O  O30  1  0.950  0.883  0.833  1.0
  O  O31  1  0.050  0.117  0.167  1.0
  O  O32  1  0.015  0.720  0.735  1.0
  O  O33  1  0.985  0.280  0.265  1.0
  O  O34  1  0.720  0.985  0.705  1.0
  O  O35  1  0.280  0.015  0.295  1.0
[/CIF]
.
The material structure described by Ta9V2O25 crystallizes in the tetragonal I4/m space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(5) and four O(6,6) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), one O(6), one O(7), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 1-27°. In the third Ta site, Ta(3) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(1) atoms to form distorted TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent V(1)O4 tetrahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-27°. V(1) is bonded to four equivalent O(4) atoms to form distorted VO4 tetrahedra that share corners with four equivalent Ta(3)O6 octahedra and edges with two equivalent V(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. There are eight inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Ta(3) and two equivalent V(1) atoms. In the second O site, O(5) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the third O site, O(6) is bonded in a linear geometry to one Ta(1) and one Ta(2) atom. In the fourth O site, O(6) is bonded in a linear geometry to one Ta(1) and one Ta(2) atom. In the fifth O site, O(7) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. In the sixth O site, O(1) is bonded in a distorted T-shaped geometry to one Ta(2) and two equivalent Ta(3) atoms. In the seventh O site, O(2) is bonded in a distorted T-shaped geometry to one Ta(3) and two equivalent Ta(2) atoms. In the eighth O site, O(3) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. is represented by the CIF file [CIF]
data_Ta9V2O25
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.436
_cell_length_b   11.436
_cell_length_c   11.436
_cell_angle_alpha   91.740
_cell_angle_beta   91.740
_cell_angle_gamma   159.929
_symmetry_Int_Tables_number   1
_cell_volume   505.475
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.222  0.901  0.124  1.0
  Ta  Ta2  1  0.778  0.099  0.876  1.0
  Ta  Ta3  1  0.901  0.778  0.679  1.0
  Ta  Ta4  1  0.099  0.222  0.321  1.0
  Ta  Ta5  1  0.125  0.680  0.805  1.0
  Ta  Ta6  1  0.875  0.320  0.195  1.0
  Ta  Ta7  1  0.680  0.875  0.555  1.0
  Ta  Ta8  1  0.320  0.125  0.445  1.0
  V  V9  1  0.750  0.250  0.500  1.0
  V  V10  1  0.250  0.750  0.500  1.0
  O  O11  1  0.350  0.838  0.188  1.0
  O  O12  1  0.650  0.162  0.812  1.0
  O  O13  1  0.838  0.650  0.488  1.0
  O  O14  1  0.162  0.350  0.512  1.0
  O  O15  1  0.251  0.612  0.863  1.0
  O  O16  1  0.749  0.388  0.137  1.0
  O  O17  1  0.612  0.749  0.361  1.0
  O  O18  1  0.388  0.251  0.639  1.0
  O  O19  1  0.178  0.787  0.966  1.0
  O  O20  1  0.822  0.213  0.034  1.0
  O  O21  1  0.787  0.822  0.609  1.0
  O  O22  1  0.213  0.178  0.391  1.0
  O  O23  1  0.084  0.560  0.644  1.0
  O  O24  1  0.916  0.440  0.356  1.0
  O  O25  1  0.560  0.916  0.476  1.0
  O  O26  1  0.440  0.084  0.524  1.0
  O  O27  1  0.500  0.500  0.000  1.0
  O  O28  1  0.117  0.950  0.066  1.0
  O  O29  1  0.883  0.050  0.934  1.0
  O  O30  1  0.950  0.883  0.833  1.0
  O  O31  1  0.050  0.117  0.167  1.0
  O  O32  1  0.015  0.720  0.735  1.0
  O  O33  1  0.985  0.280  0.265  1.0
  O  O34  1  0.720  0.985  0.705  1.0
  O  O35  1  0.280  0.015  0.295  1.0
[/CIF]
.