The compound described by YTa3O9 crystallizes in the monoclinic C2/m space group. Y(1) is bonded to one O(6), two equivalent O(1), two equivalent O(5), three equivalent O(2), and four equivalent O(4) atoms to form distorted YO12 cuboctahedra that share corners with three equivalent Y(1)O12 cuboctahedra, faces with two equivalent Y(1)O12 cuboctahedra, faces with two equivalent Ta(3)O6 octahedra, faces with three equivalent Ta(1)O6 octahedra, and faces with three equivalent Ta(2)O6 octahedra. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, and faces with three equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-22°. In the second Ta site, Ta(2) is bonded to one O(2), one O(7), two equivalent O(1), and two equivalent O(4) atoms to form distorted TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(3)O6 octahedra, and faces with three equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-22°. In the third Ta site, Ta(3) is bonded to one O(6), one O(7), two equivalent O(1), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(3)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, and faces with two equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-14°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Y(1), one Ta(2), and one Ta(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Y(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Y(1), one Ta(1), and one Ta(2) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Y(1), one Ta(1), and one Ta(3) atom. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Y(1) and two equivalent Ta(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. is represented by the CIF card [CIF]
data_YTa3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.858
_cell_length_b   8.844
_cell_length_c   8.865
_cell_angle_alpha   66.173
_cell_angle_beta   63.276
_cell_angle_gamma   26.549
_symmetry_Int_Tables_number   1
_cell_volume   371.129
_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
  Y  Y0  1  0.315  0.047  0.007  1.0
  Y  Y1  1  0.685  0.953  0.993  1.0
  Ta  Ta2  1  0.074  0.521  0.257  1.0
  Ta  Ta3  1  0.249  0.516  0.736  1.0
  Ta  Ta4  1  0.417  0.500  0.248  1.0
  Ta  Ta5  1  0.751  0.484  0.264  1.0
  Ta  Ta6  1  0.583  0.500  0.752  1.0
  Ta  Ta7  1  0.926  0.479  0.743  1.0
  O  O8  1  0.097  0.005  0.233  1.0
  O  O9  1  0.172  0.485  1.000  1.0
  O  O10  1  0.000  0.500  0.500  1.0
  O  O11  1  0.431  0.002  0.209  1.0
  O  O12  1  0.073  0.494  0.791  1.0
  O  O13  1  0.266  0.485  0.235  1.0
  O  O14  1  0.500  0.500  0.000  1.0
  O  O15  1  0.337  0.492  0.498  1.0
  O  O16  1  0.749  0.002  0.235  1.0
  O  O17  1  0.432  0.467  0.767  1.0
  O  O18  1  0.568  0.533  0.233  1.0
  O  O19  1  0.251  0.998  0.765  1.0
  O  O20  1  0.828  0.515  0.000  1.0
  O  O21  1  0.663  0.508  0.502  1.0
  O  O22  1  0.734  0.515  0.765  1.0
  O  O23  1  0.927  0.506  0.209  1.0
  O  O24  1  0.569  0.998  0.791  1.0
  O  O25  1  0.903  0.995  0.767  1.0
[/CIF]
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The compound described by YTa3O9 crystallizes in the monoclinic C2/m space group. Y(1) is bonded to one O(6), two equivalent O(1), two equivalent O(5), three equivalent O(2), and four equivalent O(4) atoms to form distorted YO12 cuboctahedra that share corners with three equivalent Y(1)O12 cuboctahedra, faces with two equivalent Y(1)O12 cuboctahedra, faces with two equivalent Ta(3)O6 octahedra, faces with three equivalent Ta(1)O6 octahedra, and faces with three equivalent Ta(2)O6 octahedra. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, and faces with three equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-22°. In the second Ta site, Ta(2) is bonded to one O(2), one O(7), two equivalent O(1), and two equivalent O(4) atoms to form distorted TaO6 octahedra that share corners with three equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(3)O6 octahedra, and faces with three equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-22°. In the third Ta site, Ta(3) is bonded to one O(6), one O(7), two equivalent O(1), and two equivalent O(5) atoms to form TaO6 octahedra that share  a cornercorner with one Ta(3)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, corners with three equivalent Ta(2)O6 octahedra, and faces with two equivalent Y(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-14°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Y(1), one Ta(2), and one Ta(3) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Y(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Y(1), one Ta(1), and one Ta(2) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to one Y(1), one Ta(1), and one Ta(3) atom. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Y(1) and two equivalent Ta(3) atoms. In the seventh O site, O(7) is bonded in a linear geometry to one Ta(2) and one Ta(3) atom. is represented by the CIF card [CIF]
data_YTa3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.858
_cell_length_b   8.844
_cell_length_c   8.865
_cell_angle_alpha   66.173
_cell_angle_beta   63.276
_cell_angle_gamma   26.549
_symmetry_Int_Tables_number   1
_cell_volume   371.129
_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
  Y  Y0  1  0.315  0.047  0.007  1.0
  Y  Y1  1  0.685  0.953  0.993  1.0
  Ta  Ta2  1  0.074  0.521  0.257  1.0
  Ta  Ta3  1  0.249  0.516  0.736  1.0
  Ta  Ta4  1  0.417  0.500  0.248  1.0
  Ta  Ta5  1  0.751  0.484  0.264  1.0
  Ta  Ta6  1  0.583  0.500  0.752  1.0
  Ta  Ta7  1  0.926  0.479  0.743  1.0
  O  O8  1  0.097  0.005  0.233  1.0
  O  O9  1  0.172  0.485  1.000  1.0
  O  O10  1  0.000  0.500  0.500  1.0
  O  O11  1  0.431  0.002  0.209  1.0
  O  O12  1  0.073  0.494  0.791  1.0
  O  O13  1  0.266  0.485  0.235  1.0
  O  O14  1  0.500  0.500  0.000  1.0
  O  O15  1  0.337  0.492  0.498  1.0
  O  O16  1  0.749  0.002  0.235  1.0
  O  O17  1  0.432  0.467  0.767  1.0
  O  O18  1  0.568  0.533  0.233  1.0
  O  O19  1  0.251  0.998  0.765  1.0
  O  O20  1  0.828  0.515  0.000  1.0
  O  O21  1  0.663  0.508  0.502  1.0
  O  O22  1  0.734  0.515  0.765  1.0
  O  O23  1  0.927  0.506  0.209  1.0
  O  O24  1  0.569  0.998  0.791  1.0
  O  O25  1  0.903  0.995  0.767  1.0
[/CIF]
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