The material structure described by PrTa3O9 crystallizes in the monoclinic P2_1/m space group. Pr(1) is bonded in a 8-coordinate geometry to one O(3), one O(6), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 26-47°. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 28-47°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Pr(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pr(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Pr(1) and two equivalent Ta(1) atoms to form a mixture of distorted corner and edge-sharing OPr2Ta2 tetrahedra. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Pr(1) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_PrTa3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.572
_cell_length_b   5.440
_cell_length_c   8.220
_cell_angle_alpha   87.611
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   338.270
_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
  Pr  Pr0  1  0.250  0.967  0.434  1.0
  Pr  Pr1  1  0.750  0.033  0.566  1.0
  Ta  Ta2  1  0.493  0.526  0.700  1.0
  Ta  Ta3  1  0.007  0.526  0.700  1.0
  Ta  Ta4  1  0.993  0.474  0.300  1.0
  Ta  Ta5  1  0.000  0.000  0.000  1.0
  Ta  Ta6  1  0.507  0.474  0.300  1.0
  Ta  Ta7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.952  0.683  0.122  1.0
  O  O9  1  0.048  0.317  0.878  1.0
  O  O10  1  0.054  0.155  0.213  1.0
  O  O11  1  0.750  0.355  0.338  1.0
  O  O12  1  0.037  0.268  0.533  1.0
  O  O13  1  0.446  0.155  0.213  1.0
  O  O14  1  0.548  0.683  0.122  1.0
  O  O15  1  0.537  0.732  0.467  1.0
  O  O16  1  0.750  0.084  0.015  1.0
  O  O17  1  0.946  0.845  0.787  1.0
  O  O18  1  0.750  0.444  0.688  1.0
  O  O19  1  0.554  0.845  0.787  1.0
  O  O20  1  0.250  0.556  0.312  1.0
  O  O21  1  0.452  0.317  0.878  1.0
  O  O22  1  0.963  0.732  0.467  1.0
  O  O23  1  0.463  0.268  0.533  1.0
  O  O24  1  0.250  0.645  0.662  1.0
  O  O25  1  0.250  0.916  0.985  1.0
[/CIF]
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The material structure described by PrTa3O9 crystallizes in the monoclinic P2_1/m space group. Pr(1) is bonded in a 8-coordinate geometry to one O(3), one O(6), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(2), one O(3), one O(6), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 26-47°. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 28-47°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Pr(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pr(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to two equivalent Pr(1) and two equivalent Ta(1) atoms to form a mixture of distorted corner and edge-sharing OPr2Ta2 tetrahedra. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Pr(1) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_PrTa3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.572
_cell_length_b   5.440
_cell_length_c   8.220
_cell_angle_alpha   87.611
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   338.270
_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
  Pr  Pr0  1  0.250  0.967  0.434  1.0
  Pr  Pr1  1  0.750  0.033  0.566  1.0
  Ta  Ta2  1  0.493  0.526  0.700  1.0
  Ta  Ta3  1  0.007  0.526  0.700  1.0
  Ta  Ta4  1  0.993  0.474  0.300  1.0
  Ta  Ta5  1  0.000  0.000  0.000  1.0
  Ta  Ta6  1  0.507  0.474  0.300  1.0
  Ta  Ta7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.952  0.683  0.122  1.0
  O  O9  1  0.048  0.317  0.878  1.0
  O  O10  1  0.054  0.155  0.213  1.0
  O  O11  1  0.750  0.355  0.338  1.0
  O  O12  1  0.037  0.268  0.533  1.0
  O  O13  1  0.446  0.155  0.213  1.0
  O  O14  1  0.548  0.683  0.122  1.0
  O  O15  1  0.537  0.732  0.467  1.0
  O  O16  1  0.750  0.084  0.015  1.0
  O  O17  1  0.946  0.845  0.787  1.0
  O  O18  1  0.750  0.444  0.688  1.0
  O  O19  1  0.554  0.845  0.787  1.0
  O  O20  1  0.250  0.556  0.312  1.0
  O  O21  1  0.452  0.317  0.878  1.0
  O  O22  1  0.963  0.732  0.467  1.0
  O  O23  1  0.463  0.268  0.533  1.0
  O  O24  1  0.250  0.645  0.662  1.0
  O  O25  1  0.250  0.916  0.985  1.0
[/CIF]
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