The structure described by Tb3TaO7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(3), two equivalent O(1), and four equivalent O(2) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra, corners with three equivalent Tb(1)O7 pentagonal bipyramids, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Tb(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 42°. In the second Tb site, Tb(2) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. Ta(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Tb(1)O7 pentagonal bipyramids, and edges with four equivalent Tb(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 33°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Tb(1) and two equivalent Tb(2) atoms to form a mixture of edge and corner-sharing OTb4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(1), and one Ta(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Tb(1) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.495
_cell_length_b   6.495
_cell_length_c   7.557
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   110.379
_symmetry_Int_Tables_number   1
_cell_volume   298.804
_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
  Tb  Tb0  1  0.515  0.055  0.250  1.0
  Tb  Tb1  1  0.945  0.485  0.750  1.0
  Tb  Tb2  1  0.000  0.000  0.000  1.0
  Tb  Tb3  1  0.000  0.000  0.500  1.0
  Tb  Tb4  1  0.055  0.515  0.250  1.0
  Tb  Tb5  1  0.485  0.945  0.750  1.0
  Ta  Ta6  1  0.500  0.500  0.000  1.0
  Ta  Ta7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.887  0.152  0.250  1.0
  O  O9  1  0.848  0.113  0.750  1.0
  O  O10  1  0.821  0.563  0.034  1.0
  O  O11  1  0.821  0.563  0.466  1.0
  O  O12  1  0.437  0.179  0.966  1.0
  O  O13  1  0.437  0.179  0.534  1.0
  O  O14  1  0.576  0.576  0.750  1.0
  O  O15  1  0.424  0.424  0.250  1.0
  O  O16  1  0.563  0.821  0.034  1.0
  O  O17  1  0.179  0.437  0.534  1.0
  O  O18  1  0.563  0.821  0.466  1.0
  O  O19  1  0.179  0.437  0.966  1.0
  O  O20  1  0.113  0.848  0.750  1.0
  O  O21  1  0.152  0.887  0.250  1.0
[/CIF]
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The structure described by Tb3TaO7 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(3), two equivalent O(1), and four equivalent O(2) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra, corners with three equivalent Tb(1)O7 pentagonal bipyramids, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Tb(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 42°. In the second Tb site, Tb(2) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. Ta(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Tb(1)O7 pentagonal bipyramids, and edges with four equivalent Tb(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 33°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Tb(1) and two equivalent Tb(2) atoms to form a mixture of edge and corner-sharing OTb4 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(1), and one Ta(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Tb(1) and two equivalent Ta(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.495
_cell_length_b   6.495
_cell_length_c   7.557
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   110.379
_symmetry_Int_Tables_number   1
_cell_volume   298.804
_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
  Tb  Tb0  1  0.515  0.055  0.250  1.0
  Tb  Tb1  1  0.945  0.485  0.750  1.0
  Tb  Tb2  1  0.000  0.000  0.000  1.0
  Tb  Tb3  1  0.000  0.000  0.500  1.0
  Tb  Tb4  1  0.055  0.515  0.250  1.0
  Tb  Tb5  1  0.485  0.945  0.750  1.0
  Ta  Ta6  1  0.500  0.500  0.000  1.0
  Ta  Ta7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.887  0.152  0.250  1.0
  O  O9  1  0.848  0.113  0.750  1.0
  O  O10  1  0.821  0.563  0.034  1.0
  O  O11  1  0.821  0.563  0.466  1.0
  O  O12  1  0.437  0.179  0.966  1.0
  O  O13  1  0.437  0.179  0.534  1.0
  O  O14  1  0.576  0.576  0.750  1.0
  O  O15  1  0.424  0.424  0.250  1.0
  O  O16  1  0.563  0.821  0.034  1.0
  O  O17  1  0.179  0.437  0.534  1.0
  O  O18  1  0.563  0.821  0.466  1.0
  O  O19  1  0.179  0.437  0.966  1.0
  O  O20  1  0.113  0.848  0.750  1.0
  O  O21  1  0.152  0.887  0.250  1.0
[/CIF]
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